Information recording-displaying card, image processing method using same, and image processor

ABSTRACT

An information recording-displaying card, includes: core sheet; and over sheet bonded to core sheet, including: a support including an amorphous polyester resin, and a reversible thermosensitive recording layer on the support, including: an electron-donating coloring compound, and an electron-accepting compound. The reversible thermosensitive recording layer is capable of forming coloring state and decolorizing state, with difference in at least one of the following: heating temperature, and cooling rate after heating. The over sheet is embossable in upper portion thereof, functions as image displaying section, and meets the following conditions (A), (B) and (C): (A) (over sheet&#39;s upper limit temperature for erasing−30° C.)&gt;(over sheet&#39;s temperature of storage elasticity E′ (1.0 E+08) Pa), (B) 10 μm or less of surface waviness WCM, and (C) 1.0 E+02 Pa≦(storage elasticity E′ of reversible thermosensitive over sheet at 180° C.)≦5.0 E+07 Pa.

CROSS-REFERENCE TO RELATED APPLICATIONS

This is a continuation of Application No. PCT/JP03/05159, filed on Apr.23, 2003.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to an information recording-displayingcard capable of displaying visibly and rewriting information by heating,an over sheet used for the information recording-displaying card, animage processing method, an image processor, and a method ofmanufacturing the information recording-displaying card.

2. Description of the Related Art

Information recording card such as a membership card, an ID card, acredit card, a cash card, an IC card and the like partly has aninformation storing section such as a magnetic tape, an IC chip and thelike. This information storing section can record an individual secretinformation, especially such as money and the like. Due to itscompactness and convenience, the information recording card iswidespread in many countries in modern society. The informationrecording card carries out reading and rewriting of the recordedinformation with a special unit, although leaving a shortcoming that thecard owner cannot visually (directly) verify the recorded information.

On the other hand, developed and used recently in the market is arewritable card capable of carrying out a temporary image forming, andcapable of erasing the image when the image is not necessary. Morespecifically, the above rewritable card is the one that can visuallydisplay the information on its surface and can rewrite the information.Some rewritable cards are provided with a magnetic information storingfunction.

The above function of the rewritable card, namely, displaying visuallyand rewriting the information as an image can be expressed by formingthe following states: Between an electron-donating compound (so-called aleuco dye) and an acid/base compound, a coloring state and adecolorizing state are relatively formed with a difference in one of thefollowing: i) a heating temperature, and ii) a cooling rate after aheating. Hereinabove, the electron-donating compound has a lactone ringin its molecular structure and may assume the coloring by making astructural change attributable to the lactone ring opened by an electrondischarge, while the acid/base compound functions as adeveloping-reducing reagent. For example, Japanese Patent ApplicationLaid-Open (JP-A) No. 2-188293 and JP-A No. 2-188294 disclose arewritable card made of a reversible recording material having such astructure that a reversible thermosensitive recording layer is disposedon a support. Herein, a resin base material for the reversiblethermosensitive recording layer contains, as main materials thereof, theelectron-donating compound and the developing-reducing reagent which aredescribed above. More specifically, the above reversible thermosensitiverecording material uses a difference in reaction rate between the acidand the base, to thereby repeat the colorings and the decolorizings.

JP-A No. 5-124360 and JP-A No. 6-210954 disclose a reversiblethermosensitive recording material having a resin base materialcontaining i) a leuco dye and ii) an electron-accepting compound havinga long-chain alkyl group as a developing agent. The developing agentwith the long-chain alkyl structure has a cohesive force, and contactsthe leuco dye or is separated from the leuco dye, thus repeating thecolorings and decolorizings.

Since sufficiently compensating for the conventional shortcoming of theinformation recording card described above, the reversiblethermosensitive recording material having the functions of displayingvisually and rewriting the information attracts attention. With this,such a card is developed and recently begins to be used in the market ashas a first function (as an image displaying section) of displayingvisually and rewriting information and a second function (as aninformation storing section) of recording and rewriting the information.Hereinafter, the above card is to be referred to as “informationrecording-displaying card.”

The above information recording-displaying card, basically, uses i) anover sheet such as a reversible thermosensitive recording material inwhich at least a reversible thermosensitive recording layer is disposedon a support, and ii) a core sheet having a function as the conventionalinformation recording card. The above information recording-displayingcard can be formed by overlapping the over sheet's support side with thecore sheet, followed by a thermo-compression bonding and the like.

The image displaying function of the above informationrecording-displaying card is carried out by the over sheet. On the otherhand, the image storing function of the above informationrecording-displaying card may vary with types of the card. Morespecifically about this: The information storing function by a magneticmaterial such as a magnetic tape can be carried out by the over sheet orthe core sheet. However, the information storing function by an IC chip,antenna coil, a magnetic stripe and the like is, in general, disposed ina thick core sheet.

Some information recording-displaying cards are thin and others arethick. Since the over sheet is thin, the thickness of the informationrecording-displaying card is ordinarily dependent on the thickness ofthe core sheet.

The information recording-displaying card recently beginning to be usedin the market is made of a combination of the following i) and ii): i) areversible thermosensitive over sheet using, as a support, apolyethylene terephthalate (PET) film, and ii) a core sheet having, as araw material, polyvinyl chloride (PVC) resin, polyvinyl chloride resinsuch as copolymer of vinyl chloride and vinyl acetate, or polycarbonateresin.

The above materials are widely used for the following reasons: Thepolyethylene terephthalate (PET) film used for the support of the oversheet is highly resistant to a solution which is made by dissolving acomposition (especially, constituting the reversible recording layer) ina solvent. The polyvinyl chloride (PVC) resin used as the core sheetmaterial is excellent in physical property, mechanical property,embossability (at character section), and the like.

The above polyvinyl chloride resin is also proper as the support of theover sheet, so as to obtain an image eraseability, in view ofexpressing, to a certain extent, a flexibility by heat.

Though being excellent as the card's raw material, the above polyvinylchloride may, from some viewpoints, cause a hydrogen chloride gas whenincinerated after being used and then scrapped, thus damaging anincinerator and reducing lifetime thereof.

Mover, movement of eliminating the polyvinyl chloride (PVC) resin isbecoming more and more active in various countries, although relationbetween the polyvinyl chloride (PVC) and dioxine is not clarified. Thepolyvinyl chloride resin is used for the informationrecording-displaying card as well as the conventional informationrecording card, in other words, has high publicity. With the abovebackground, other material replaceable with the polyvinyl chloride (PVC)is desired also domestically.

For use as the raw material for the information recording-displayingcard, a thermoplastic resin is being studied that does not containhalogen. Examples of the above thermoplastic resin include polyethyleneresin, polypropyrene resin, polyester resin, polycarbonate resin,polyacrylic resin, and the like.

Among the above, the card's base material made of polycarbonate resinand the like is highly resistant to heat, thereby, is unlikely to causedeformation attributable to heat, becoming an excellent material interms of durability. The information recording-displaying card using thepolycarbonate resin and the like is, therefore, appearing in the market.

However, being low in deformability, the polycarbonate resin is low inembossability. The reversible thermosensitive recording material forwriting-erasing by using a thermal head may lose head matching propertywith the thermal head contacting the information recording-displayingcard, thus reducing sensitivity, leading especially to deterioratederaseability, which is a shortcoming. A raw material replaceable withthe polyvinyl chloride resin is conventionally not found.

On the other hand, a unity which is the over sheet bonded with the coresheet is to be embossed. The thus formed “emboss marking” is to bemarked on the information recording-displaying card, to thereby makepersonal information identifiable, which is important in terms ofconvenience and usefulness. Especially, a thick card such as the creditcard, the bank card and the like is to be provided with the “embossmarking,” which is indispensable in the modern society. In sum, theembossing is more and more required from users and various industries.

The above “emboss marking” is mainly used for card number, expiration,owner's name and the like, and has such a function as to be copied witha roller, by interposing the card into a copy voucher for reckoning at astore and the like. The above use of the “emboss marking” is prevalentdomestically and overseas.

The polyethylene terephthalate (PET) film used for the support of theover sheet is so rigid as to have low deformation by an appliedpressure, thereby, has an extremely low embossability. With this, evenwhen the polyvinyl chloride resin used for the core sheet has a goodembossability and the embossing is carried out from upside of the oversheet, the over sheet using the polyethylene terephthalate (PET) filmmay cause an insufficient “emboss marking.” Moreover, the polyethyleneterephthalate (PET) film becoming too thick may cause breaking of thecard in the embossing.

Especially, a thick card with the above non-contact IC chip, antennacoil, magnetic stripe and the like embedded therein cannot sufficientlyabsorb irregularity thereof, thereby making it impossible to flatten thecard's surface. With this, the above thick card cannot smoothly carryout rewriting of the recording by the thermal head and the like,therefore, as the case may be, forcibly increases printing pressure andtemperature. As a result, the above thick card may have failures such ashaving scratches, having remaining gouge, causing deformation, and thelike, thus limiting application and manufacturing methods, and therebyfinding difficulty in using manufacturing steps of the general-purposecard.

The information recording-displaying card which is recently beginning tobe used in the market has the following structure. The embossing iscarried out in an embossable space formed on the core sheet's surfacewhich space is free from the over sheet. In this structure, the oversheet bonded to the core sheet is smaller in size than the core sheet'ssurface. The above over sheet is to be bonded to the core sheet suchthat the “emboss marking” can be disposed in the embossable space freefrom the over sheet.

The above method is limited in terms of manufacturing since, forexample, the over sheet reduced in size is to be accurately bonded tothe core sheet, moreover, the above method is limited in terms of anarea for the over sheet's image display function, which areshortcomings.

In sum, the embossing cannot be carried out for a unity having the oversheet bonded to the entire face of the core sheet, making an informationrecording-displaying card without the “emboss marking.”

The reversible thermosensitive recording material used as the over sheetis “thermosensitive” which is a special material. In each of the stepsincluding i) overlapping the over sheet (having the above specialproperty) on the core sheet, ii) uniting the over sheet with the coresheet by pressing-heating, and iii) completing the embossing, it may bedifficult to manufacture the information recording-displaying cardwithout influencing the above special property, namely, “reversiblethermosensitivity.”

Moreover, the polyethylene terephthalate film used as the support of theover sheet is made of a material which is higher in heat resistance andsmaller in heat deformation than the polycarbonate resin. Therefore,applying a thermal head as a heating unit to a surface of the above oversheet of the information recording-displaying card beginning to be usedin the market may cause very little deformation by the heat. This maymake the adhesion between the thermal head's face and the over sheer'ssurface insufficient, thus losing head matching at the heat applicationand thereby decreasing the sensitivity. With this, especially theeraseability may become low, namely, an insufficient image eraseabilityis caused, which is a shortcoming.

The present inventors have studied the known data related to the abovetype of the information recording-displaying card, as a result, to findthat any of the known data are free from description of theembossability, and image eraseability involved with the embossability.

Described below are specific examples of the informationrecording-displaying cards disclosed in cited patent documents.

Firstly, for example, JP-A No. 2001-341427 (page 2 to page 4, example 1)discloses an over sheet which is a reversible recording film having thefollowing structure. A print layer, a transparent support having lighttransmission of 50% or more, a reversible recording layer, and aprotective layer are disposed on a support. A thick informationrecording-displaying card is disclosed having the support side unitedwith a core sheet by using an adhesive. However, JP-A No. 2001-341427(page 2 to page 4, example 1) does not describe embossability at all.

Material usable for the above support and the above transparent supportare described (likewise between the two) as follows: “a plastic film isapplicable thereto which is rigid, namely, excellent in heat resistance,tensile strength and the like,” and “selectable thickness in a rangefrom 8.5 μm to 300 μm, preferably 8.5 μm to about 250 μm.” Specificexamples of the material include polyethylene terephthalate (PET) film,polyethylene naphthalate (PEN) film, polyimide (PI) film, polyphenylenesulfide (PPS) film, and the like. Moreover, the transparent support ismade of materials such as vinyl chloride film, PET-G film, andpolycarbonate and the like.

JP-A No. 2001-341427 (page 2 to page 4, example 1) describes that theabove films exemplified are made of plastic which is rigid, namely,excellent in tensile strength and the like. In view of embossability,however, JP-A No. 2001-341427 (page 2 to page 4, example 1) includesthose evidently not embossable, judging from the description of anunrigid film and too rigid a film, and the description of a smallthermal deformation and a large thermal deformation.

In view of thickness, an example 1 in JP-A No. 2001-341427 (page 2 topage 4, example 1) does not describe thickness of polyethyleneterephthalate film used as the support but describes that thetransparent support uses a transparent polyethylene terephthalate filmhaving thickness of 25 μm, which is too thick for the embossing of theover sheet.

Moreover, the over sheet itself that is formed according to this example1 of JP-A No. 2001-341427 (page 2 to page 4, example 1) has thepolyethylene terephthalate film as the support and as the transparentsupport, thus losing the head matching at the heat application andthereby decreasing the sensitivity. With this, especially the imageeraseability may become low.

As a core sheet material, JP-A No. 2001-341427 (page 2 to page 4,example 1) describes examples including vinyl chloride resin, PET-Gtypical of polyester resin, polycarbonate resin, which are used alone orin combination. No description of the embossability in JP-A No.2001-341427 (page 2 to page 4, example 1) proves impossibility of theembossing.

For the next example, JP-A No. 2000-137782 (example 1 and example 2)discloses a card's base material (core sheet) which is a thermoplasticresin sheet having low crystal property of 5% or less. A thickinformation recording-displaying card is disclosed which is a unity ofthe above card's base material (core sheet) bonded with a reversiblethermosensitive recording tape (over sheet). The reversiblethermosensitive recording tape hereinabove is provided with a reversiblethermosensitive recording layer (containing a leuco compound and adeveloping agent) on a transparent PET film.

JP-A No. 2000-137782 (example 1 and example 2) is, however, free fromany description of embossing. Judging from the thick PET film (25 μm inthickness in an example 1, and 38 μm thick in an example 2), theinformation recording-displaying card is not embossable and has a pooreraseability.

For the next example, JP-A No. 11-154210 (example) discloses i) a sheet(core sheet) incorporating therein an IC chip module, and ii) areversible thermosensitive recording sheet (over sheet) provided with areversible thermosensitive recording layer (containing a leuco dye and adeveloping agent) on a film, which two sheets are opposed to each other.To a gap between the core sheet and the over sheet, a resin is injectedand thereby the two sheets are bonded with each other, thus forming anIC card (thick information recording-displaying card). However, JP-A No.11-154210 (example) is free from any description of embossing.

For the next example, JP-A No. 2001-88443 (example) discloses arecording medium used for mass production adopting a Kanban (signboard)method, which recording medium has a base material, a reversiblethermosensitive recording layer (containing a leuco compound and adeveloping agent) on the base material, and a protective layer. Varioustypes of plastic films are exemplified as the base material. A white PETwhich is the base material in each example has a thickness of 188 μm,250 μm and 350 μm, proving no attention is paid to embossing.

JP-A No. 2000-137782 (example 1 and example 2), JP-A No. 11-154210(example) and JP-A No. 2001-88443 (example) described above disclosevarious specific examples of materials for the support constituting theover sheet, and materials for raw materials constituting the core sheet.In view of the embossing, like JP-A No. 2001-341427 (page 2 to page 4,example 1), some materials thus exemplified may cause a small thermaldeformation and other materials thus exemplified may cause a largethermal deformation, i.e., including those embossable and notembossable.

Summarizing the above, the information recording-displaying cardbeginning to be used in the market is not embossable on the over sheet'sface. For the embossing, therefore, the image display area is reduced,making the image eraseability insufficient and causing environmentalpollution in the scrapping and disposal.

The information recording-displaying card disclosed in the known data isnot studied in view of the embossing or the image eraseability involvedwith the embossability. Moreover, no proposal is made in the above knowndata for solving the environmental pollution in the scrapping anddisposal.

For bringing about a sufficient embossability to the informationrecording-displaying card, each of the over sheet and the core sheetconstituting the information recording-displaying card, and the unity ofthe over sheet and the core sheet are to have the embossability. Theconventionally known product and the conventionally known data are freefrom the above viewpoint.

By patent documents and the like, various proposals are conventionallymade in terms of the reversible thermosensitive recording material. Theembossability is, however, not suggested or raised at all in the abovepatent documents and the like. Not to mention, the embossability of anover sheet of an information recording-displaying card is not suggestedor raised at all. In sum, securing embossability in this technical fieldand improving the image eraseability involved with the embossability arenew issues.

In terms of the embossability, for example, JP-A No. 11-240262 (claims)discloses a heated transfer card having an acceptor layer disposed on acard's base material. More specifically, a dye in JP-A No. 11-240262(claims) is contained in a heat transfer film in the field ofheating-melting transfer recording or a sublimating transfer recording,instead of the reversible thermosensitive recording. The dye is to bemelted or sublimated by a heat, and then is received or fixed by theacceptor layer.

The proposal in JP-A No. 11-240262 (claims) uses a special polyester forthe card's base material, and a polyester copolymer is used for theacceptor layer which copolymer is made by copolymerizing a reactivesilicone polymer. With the above, the moldability such as embossabilityof the heated transfer card is improved. As a matter of course, however,no description is made of accomplishment of the embossability withoutinfluencing the special property (namely, “reversiblethermosensitivity”) which is the image eraseability of the over sheet.

By patent documents and the like, many proposals are conventionally madein terms of the reversible thermosensitive recording material. Theembossability is, however, not suggested or raised at all in the abovepatent documents and the like. Not to mention, the embossability of anover sheet of an information recording-displaying card is not suggestedor raised at all. In sum, securing the embossability in this technicalfield and improving the repetition durability involved with theembossability are new issues.

Objects and Advantages

It is an object of the present invention to provide an informationrecording-displaying card that is excellent in embossability anddisplayed-image eraseability, easy to scrap and dispose, and is freefrom causing an environmental pollution in the scrapping and disposal.It is anther object of the present invention to provide an imageprocessing method and an image processor for forming an image anderasing the image by using an over sheet and the informationrecording-displaying card each of which is made of a reversiblethermosensitive recording material that is excellent in embossabilityand displayed-image eraseability. It is still another object of thepresent invention to provide a method of manufacturing the informationrecording-displaying card.

SUMMARY OF THE INVENTION

Hereinafter described are measures for accomplishing the above objects.

A first aspect of the present invention provides an informationrecording-displaying card, comprising: a core sheet; and an over sheetbonded to the core sheet, wherein the over sheet comprises: a supportwhich comprises an amorphous polyester resin, and a reversiblethermosensitive recording layer disposed on the support, wherein thereversible thermosensitive recording layer comprises: anelectron-donating coloring compound, and an electron-accepting compound.The reversible thermosensitive recording layer is capable of relativelyforming a coloring state and a decolorizing state, with a difference inat least one of the following: a heating temperature, and a cooling rateafter a heating. The over sheet is embossable in an upper portionthereof, functions as an image displaying section, and meets thefollowing condition (A), condition (B) and condition (C): condition (A)(the over sheet's upper limit temperature for erasing−30° C.)>(the oversheet's temperature of a storage elasticity E′ (1.0 E+08) Pa), condition(B) 10 μm or less of a surface waviness WCM, and condition (C) 1.0 E+04Pa≦(the storage elasticity E′ of the reversible thermosensitive oversheet at 180° C.)≦5.0 E+07 Pa.

A second aspect of the present invention according to the first aspectprovides that the temperature of the storage elasticity E′ (1.0 E+08) Paof the over sheet is less than 140° C.

A third aspect of the present invention according to the first aspectprovides that the over sheet is bonded to substantially an entire faceof the core sheet.

A fourth aspect of the present invention according to the first aspectprovides that the support is one of the following: an amorphouspolyester resin, and a polymer alloy which comprises an amorphouspolyester resin and a polycarbonate resin.

A fifth aspect of the present invention according to the first aspectprovides that a barrier layer is interposed between the support and thereversible thermosensitive recording layer.

A sixth aspect of the present invention according to the fifth aspectprovides that the barrier layer is formed by bonding a resin film.

A seventh aspect of the present invention according to the sixth aspectprovides that the resin film of the barrier layer has a thickness of 8μm or less.

An eighth aspect of the present invention according to the sixth aspectprovides that the resin film of the barrier layer is a polyester filmsubjected to a crystallizing treatment.

A ninth aspect of the present invention according to the fifth aspectprovides that the barrier layer comprises, as a main component thereof,a resin which is capable of at least one of the following: being solublein at least one of an alcohol solvent and water, and being dispersed inat least one of the alcohol solvent and the water.

A tenth aspect of the present invention according to the first aspectprovides that the electron-donating coloring compound is a leuco dye.

An eleventh aspect of the present invention according to the firstaspect provides that the electron-accepting compound is a phenolcontaining a straight chain hydrocarbon.

A twelfth aspect of the present invention according to the first aspectprovides that the core sheet comprises at least a thermoplastic resinsheet having a thickness in a range from 0.05 mm to 5.00 mm.

A thirteenth aspect of the present invention according to the twelfthaspect provides that the core sheet is made of a materiel which issubstantially common to a material for the support constituting the oversheet.

A fourteenth aspect of the present invention according to the firstaspect provides that the information recording-displaying card comprisesan information storing section.

A fifteenth aspect of the present invention according to the fourteenthaspect provides that the information storing section is one of thefollowing: a section which comprises a magnetic material as a mainmaterial, and an IC chip.

A sixteenth aspect of the present invention according to the fourteenthaspect provides that the core sheet comprises a plurality of athermoplastic resin sheets between which an IC chip is embedded, tothereby form the information storing section.

An seventeenth aspect of the present invention according to thefourteenth aspect provides that the over sheet has the informationstoring section which comprises, as a main material therefor, a magneticmaterial.

An eighteenth aspect of the present invention according to the firstaspect provides that the information recording-displaying card has amark formed through an embossing.

A nineteenth aspect of the present invention according to the eighteenthaspect provides that the mark formed through the embossing is disposedon the over sheet.

A twentieth aspect of the present invention provides a method ofmanufacturing an information recording-displaying card, comprising:heating-pressing a core sheet and an over sheet at a melting temperatureor less of an electron-accepting compound; and bonding, thereby, theover sheet with the core sheet. The over sheet comprises: a supportwhich comprises an amorphous polyester resin, and a reversiblethermosensitive recording layer disposed on the support, wherein thereversible thermosensitive recording layer comprises: anelectron-donating coloring compound, and the electron-acceptingcompound. The reversible thermosensitive recording layer is capable ofrelatively forming a coloring state and a decolorizing state, with adifference in at least one of the following: a heating temperature, anda cooling rate after a heating. The over sheet is embossable in an upperportion thereof, functions as an image displaying section, and meets thefollowing condition (A), condition (B) and condition (C): condition (A)(the over sheet's upper limit temperature for erasing−30° C.)>(the oversheet's temperature of a storage elasticity E′ (1.0 E+08) Pa), condition(B) 10 μm or less of a surface waviness WCM, and condition (C) 1.0 E+02Pa≦(the storage elasticity E′ of the reversible thermosensitive oversheet at 180° C.)≦5.0 E+07 Pa.

A twenty-first aspect of the present invention according to thetwentieth aspect provides that the heating-pressing is carried out at150° C. or less, for bonding the over sheet with the core sheet.

A twenty-second aspect of the present invention provides an over sheet,comprising: a support which comprises an amorphous polyester resin; anda reversible thermosensitive recording layer disposed on the support,wherein the reversible thermosensitive recording layer comprises: anelectron-donating coloring compound, and an electron-accepting compound.The reversible thermosensitive recording layer is capable of relativelyforming a coloring state and a decolorizing state, with a difference inat least one of the following: a heating temperature, and a cooling rateafter a heating. The over sheet is embossable in an upper portionthereof, functions as an image displaying section, and meets thefollowing condition (A), condition (B) and condition (C): condition (A)(the over sheet's upper limit temperature for erasing−30° C.)>(the oversheet's temperature of a storage elasticity E′ (1.0 E+08) Pa), condition(B) 10 μm or less of a surface waviness WCM, and condition (C) 1.0 E+02Pa≦(the storage elasticity E′ of the reversible thermosensitive oversheet at 180° C.)≦5.0 E+07 Pa.

A twenty-third aspect of the present invention provides an imageprocessing method, comprising: heating a surface of an image displayingsection of an information recording-displaying card; and carrying outthereby at least one of the following: displaying an image, and erasingthe image. The information recording-displaying card, comprises: a coresheet; an over sheet bonded to the core sheet, wherein the over sheetcomprises: a support which comprises an amorphous polyester resin, and areversible thermosensitive recording layer disposed on the support,wherein the reversible thermosensitive recording layer comprises: anelectron-donating coloring compound, and an electron-accepting compound.The reversible thermosensitive recording layer is capable of relativelyforming a coloring state and a decolorizing state, with a difference inat least one of the following: a heating temperature, and a cooling rateafter a heating. The over sheet is embossable in an upper portionthereof, functions as an image displaying section, and meets thefollowing condition (A), condition (B) and condition (C): condition (A)(the over sheet's upper limit temperature for erasing−30° C.)>(the oversheet's temperature of a storage elasticity E′ (1.0 E+08) Pa), condition(B) 10 μm or less of a surface waviness WCM, and condition (C) 1.0 E+02Pa≦(the storage elasticity E′ of the reversible thermosensitive oversheet at 180° C.)≦5.0 E+07 Pa.

A twenty-fourth aspect of the present invention according to thetwenty-third aspect provides that a thermal head is used for thedisplaying of the image.

A twenty-fifth aspect of the present invention according to thetwenty-third aspect provides that one of a thermal head and a ceramicheater is used for the erasing of the image.

A twenty-sixth aspect of the present invention according to thetwenty-third aspect provides that the thermal head is used for thedisplaying and the erasing of the image, and an over writing is carriedout by the erasing of the image and a displaying of a new image.

A twenty-seventh aspect of the present invention provides an imageprocessor, comprising: at least one of the following: an imagedisplaying unit for displaying an image to an informationrecording-displaying card; an image erasing unit for erasing the image;and an image displaying-erasing unit for displaying and erasing theimage. The information recording-displaying card comprises: a coresheet; an over sheet bonded to the core sheet, wherein the over sheetcomprises: a support which comprises an amorphous polyester resin, and areversible thermosensitive recording layer disposed on the support,wherein the reversible thermosensitive recording layer comprises: anelectron-donating coloring compound, and an electron-accepting compound.The reversible thermosensitive recording layer is capable of relativelyforming a coloring state and a decolorizing state, with a difference inat least one of the following: a heating temperature, and a cooling rateafter a heating. The over sheet is embossable in an upper portionthereof, functions as an image displaying section, and meets thefollowing condition (A), condition (B) and condition (C): condition (A)(the over sheet's upper limit temperature for erasing−30° C.)>(the oversheet's temperature of a storage elasticity E′ (1.0 E+08) Pa), condition(B) 10 μm or less of a surface waviness WCM, and condition (C) 1.0 E+02Pa≦(the storage elasticity E′ of the reversible thermosensitive oversheet at 180° C.)≦5.0 E+07 Pa.

A twenty-eighth aspect of the present invention according to thetwenty-seventh aspect provides that the image processor comprises atleast the image displaying unit, and that the image displaying unit is athermal head.

A twenty-ninth aspect of the present invention according to thetwenty-seventh aspect provides that the image processor comprises atleast the image erasing unit, and that the image erasing unit is one ofa thermal head and a ceramic heater.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1A and FIG. 1B explain a method of forming an information recordingcard according to an embodiment under the present invention, in whichFIG. 1A is a cross sectional view of a state before heating-pressing theinformation recording card according to the embodiment under the presentinvention, and FIG. 1B is a cross sectional view of a state after theheating-pressing.

FIG. 2 shows a coloring property and a decolorizing property of areversible thermosensitive recording medium under the present invention.

FIG. 3 is a cross sectional view of a state before the heating-pressing,so as to exemplify a method of manufacturing an IC card which is anexample of an information recording-displaying card under the presentinvention.

FIG. 4 is a cross sectional view of a state of the IC card in FIG. 3,after the heating-pressing and a subsequent embossing.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

To solve the above issue, the present inventors studied repeatedly anover sheet and a core sheet which constitute an informationrecording-displaying card, mainly, the over sheet which is a reversiblethermosensitive recording material, thus coming up with the presentinvention.

The above main focus on the over sheet is due to its recording materialhaving a special property of “reversible thermosensitivity.” Morespecific description is to be made below. The above special property ofthe over sheet may be influenced by a thermal energy or a mechanicalenergy which may be caused in a step of heating-pressing for uniting theover sheet with the core sheet, and a step of embossing the thusobtained unity. In this case, an image displaying function of the unitymay be decreased or lost. The present inventors, therefore, have come upwith the present invention to overcome the above possible shortcoming.

The above information recording-displaying card under the presentinvention may not be decreased in its function of an image displayingsection, even though provided with an “emboss marking” on the over sheetthrough the embossing. Moreover, the above informationrecording-displaying card under the present invention can be subjectedto another embossing after the image is displayed on the imagedisplaying section.

The information recording-displaying card under the present inventioncomprises: a core sheet, an over sheet where the core sheet and the oversheet are bonded with each other. The over sheet comprises a support anda reversible thermosensitive recording layer disposed on the support,where the support comprises an amorphous polyester resin while thereversible thermosensitive recording layer comprises anelectron-donating coloring compound, and an electron-accepting compound.The reversible thermosensitive recording layer is capable of relativelyforming a coloring state and a decolorizing state with a difference inat least one of the following: i) a heating temperature and ii) acooling rate after a heating. Moreover, the over sheet functions as animage displaying section and meets the following condition (A),condition (B) and condition (C). As long as having embossability on theover sheet, the information recording-displaying card under the presentinvention is not specifically limited. In the following condition (A),condition (B) and condition (C), “1.0 E+08” denotes “1.0×10⁸,” “1.0E+02” denotes “1.0×10²,” and “5.0 E+07” denotes “5.0×10⁷.” Moreover, thetemperature of storage elasticity E′ (1.0 E+08) Pa denotes a temperaturefor obtaining the storage elasticity of E′ (1.0 E+08) Pa.

-   Condition (A) (over sheet's upper limit temperature for erasing    image−30° C.)>(over sheet's temperature of storage elasticity E′    (1.0 E+08) Pa),-   Condition (B) 10 μm or less of a surface waviness WCM (Maximum    height of Waviness Profile), and-   Condition (C) 1.0 E+02 Pa≦(storage elasticity E′ of reversible    thermosensitive over sheet at 180° C.)≦5.0 E+07 Pa.

Hereinafter described is the condition (A), the condition (B) and thecondition (C) which are, in combination, to be met by the over sheet ofthe information recording-displaying card which over sheet is bondedwith the core sheet, under the present invention.

-   Condition (A) (over sheet's upper limit temperature for erasing    image−30° C.)>(over sheet's temperature of storage elasticity E′    (1.0 E+08) Pa)-   Condition (B) 10 μm or less of surface waviness WCM-   Condition (C) 1.0 E+02 Pa≦(storage elasticity E′ of reversible    thermosensitive over sheet at 180° C.)≦5.0 E+07 Pa The condition (A)    (over sheet's upper limit temperature for erasing image−30°    C.)>(temperature of storage elasticity E′ (1.0 E+08) Pa) is    necessary for the information recording-displaying card under the    present invention to secure an excellent property of image    eraseability.

The reversible thermosensitive recording material containing the leucodye (electron-donating coloring compound) and the developing agent(electron-accepting compound) under the present invention defines, ingeneral, an inherent image-erasing temperature range, and therefore, theupper limit temperature for erasing image is, in general, attributableto a melting point of the developing agent contained in the reversiblethermosensitive recording material which is the over sheet.

The condition (A) denotes that the (over sheet's upper limit temperaturefor erasing image−30° C.) is needed to be more than the (over sheet'stemperature of storage elasticity E′ (1.0 E+08) Pa).

Especially, the over sheet's temperature of storage elasticity E′ (1.0E+08) Pa is preferably less than 140° C. for an excellent eraseability.

Under the condition (A), the above stable image eraseability isconsidered to be attributable to an improved adhesion between a heatingunit (such as a thermal head) and the over sheet's surface.

The “over sheet's upper limit temperature for erasing image” maybasically be determined by a melting point of a developing agent of areversible thermosensitive material. Measurement thereof may be carriedout in the following steps: contacting the over sheet with a hot plateof 180° C. for a rapid quenching, forming thereby a saturated coloringimage, pressing thereafter by means of a heat slope tester HG-100 (madeby TOYO SEIKI KOGYO CO., LTD.), more specifically, pressing heat plates(5° C. stepwise temperatures) to the over sheet under a pressure of 1Kgf/cm for 1 second. With this, an erasable upper limit temperature canbe obtained.

The “temperature of storage elasticity E′ (1.0 E+08) Pa” may becalculated in the following steps: carrying out a tensile test with“Viscosity-Elasticity Spectrometer” made by IWAMOTO SEISAKUSHO,measuring temperature dispersion of a dynamic viscosity-elasticity in arange of temperature from −100° C. to 200° C. (3° C. stepwisetemperatures) at a frequency of 1 Hz, and calculating the storageelasticity E′ as a real number item. The temperature was obtained whenthe storage elasticity E′ reached 1.0 E+08. The temperature of storageelasticity E′ (1.0 E+08) Pa may influence the durability of therepeatedly-used information recording-displaying card, and is preferredto be relatively high, especially preferably 80° C. or more for therepetition durability.

The temperature of storage elasticity E′ (1.0 E+08) Pa less than 80° C.may cause a large curl after several printing operations, which is notpractically preferable.

The amorphous polyester resin used as the support constituting the oversheet under the present invention may be obtained by, for example,dehydrated-condensed body (aromatic dicarboxylic acid component withdiol component). The above support made of the above amorphous polyesterresin can improve flexibility when heated.

Applying a heat to the surface of the over head by means of the thermalhead as an erasing-heating unit may improve flexibility of the overhead, thus bettering adhesion of the over sheet to the thermal head. Asa result, the image eraseability can be improved. The above flexibilityis largely influenced by the support. In this case, however, theflexibly of the support may not necessarily determine the entireflexibility of the over sheet.

The condition (B) (10 μm or less of a surface waviness WCM) is necessaryfor the information recording-displaying card under the presentinvention to secure an excellent image eraseability as well as anexcellent image visibility.

The surface waviness WCM of the over sheet under the present inventionwhich sheet is provided with the reversible thermosensitive recordinglayer on the support may cause a large influence on the imageeraseability, image visibility, and the like. Therefore, the surfacewaviness WCM is preferred to be as smooth as possible, specifically,about 10 μm or less. More than 10 μm may cause an insufficient adhesionbetween the over sheet and the heating unit, thereby decreasing theimage eraseability, leading to deteriorated visibility and appearance.

The surface waviness WCM hereinabove signifies a maximum filterwaviness. Specifically, in a section extracting a standard length(measurement length 5.0 mm) from a filter waviness curve, the surfacewaviness WCM denotes a gap between two lines (parallel to an averageline) interposing therebetween the above extracted section. The value ofthe surface waviness WCM under the present invention denotes ameasurement by a surface roughness measuring apparatus made by TOKYOSEIMITSU.

The above surface waviness is largely influenced by i) material for thesupport, ii) thickness of the support, iii) conditions for manufacturingthe over sheet, and the like. When the amorphous polyester is used asthe support of the over sheet under the present invention, drying at100° C. or more after coating the thermosensitive recording layer on thesupport may be a cause for deformation. Moreover, the support using theamorphous polyester film which has high solubility in solvent may beeroded with the solution for forming the thermosensitive recording layer(namely, solutions using solvent such as MEK, toluene, ethyl acetate,THK (tetrahydrofuran) and the like which are used generally), thusdeforming the support and roughing the surface of the support, which isnot preferable.

The condition (C) 1.0 E+02 Pa≦(the storage elasticity E′ of thereversible thermosensitive over sheet at 180° C.)≦5.0 E+07 Pa isnecessary for the over sheet constituting the informationrecording-displaying card under the present invention to secure anexcellent embossability.

As described above, in the modern society, it is practicallyindispensable that the credit card, the cash card and the like aremarked with “emboss marking” which can be formed by embossing.

The over sheet, the core sheet and the information recording-displayingcard (which is a unity of the two sheets) may influence the respectiveembossabilities thereof. The over sheet which is required to bring abouta sufficient image-displaying function and to impart the embossabilityis especially important under the present invention. Thereby, the oversheet is especially studied under the present invention and conditionsthereof have been determined.

Whether or not embossable depends on “softness” in the machiningtemperature range of the over sheet. Under the present invention, the“softness” is expressed by the storage elasticity E′ of the over sheet.More specifically, it is necessary to use the over sheet having thestorage elasticity E′ of 5.0 E+07 Pa or less at 180° C. Meeting theabove range may carry out the embossing advantageously.

Embossing with the storage elasticity E′ more than 5.0 E+07 Pa at 180°C. may cause layer-to-layer peeling attributable to braking of the oversheet itself, or cause warp to the finished card.

Embossing with the storage elasticity E′ less than 1.0 E+02 Pa at 180°C. may cause filming failure in the film forming, thus damaging filmconfiguration in the forming process thereof, which is not preferable.

As described afterward, disposing a barrier layer on the support may bein need of attention, since material, thickness and the like of thebarrier layer may influence the storage elasticity E′.

The storage elasticity E′ of the reversible thermosensitive over sheetat 180° C. is to be measured and calculated according to its specificmethod.

In many cases, the embossing is carried out at 180° C. or more. Withthis, the over sheet is preferred to have softness to a certain extentat 180° C. time point. After studying, the present inventors have foundthat the over sheet having the storage elasticity E′ of 5.0 E+07 Pa orless at 180° C. is sufficiently embossable.

The over sheet under the present invention is a reversiblethermosensitive recording material which has at least a reversiblethermosensitive recording layer on the support. The reversiblethermosensitive recording layer contains an electron-donating coloringcompound and an electron-accepting compound and can relatively form acoloring state and a decolorizing state, with a difference in at leastone of the following: i) a heating temperature and ii) a cooling rateafter the heating.

The material constituting the reversible thermosensitive recording layerand forming other layer(s), when necessary, such as a protective layeron the reversible thermosensitive recording layer can be accomplished bythe known reversible thermosensitive recording material.

Hereinafter described in detail is the support of the over sheet sincethe support is the most influential in the embossability and the imageeraseability under the present invention. Other technical points are tobe followed thereafter.

In view of the embossability and the image eraseability as well asunification (adhesion and heat fusibility) of the over sheet with thecore sheet, the material for the support of the over sheet under thepresent invention is a resin composition containing an amorphouspolyester resin. Specifically, the resin composition includes i) asingle type of amorphous polyester resin composition, ii) a polymeralloy resin composition of a plurality of amorphous polyester resins,iii) a polymer alloy resin composition of an amorphous polyester resinand a polycarbonate resin, iv) and the like.

Herein, the amorphous polyester resin under the present invention may beobtained by dehydrated-condensed body (aromatic dicarboxylic acidcomponent with diol component). Moreover, the amorphous polyester resinhereinabove is free from failures such as whitening (bycrystallization), fusion and the like, which may be caused in apractical heating-machining such as pressing-fusing for manufacturingthe cards. Moreover, concept of the amorphous polyester resin under thepresent invention extensively includes those having low molecularcrystal property, PBT (polybutylene terephthalate) before acrystallizing treatment, and the like.

Preferable examples of the aromatic dicarboxylic acid component becomingthe raw material for the amorphous polyester resin typically includeterephthalic acid, isophthalic acid, naphthalene dicarboxylic acid, andthe like. Otherwise, a part of the terephthalic acid may be substitutedwith other dicarboxylic acid.

Examples of the other dicarboxylic acids include oxalic acid, malonicacid, succinic acid, adipic acid, azelaic acid, sebacic acid, neopentylacid, isophthalic acid, naphthalene dicarboxylic acid, diphenyl etherdicarboxylic acid, p-oxy benzoic acid, and the like. The above otherdicarboxylic acids may be used alone or in combination of two or more.Moreover, the amount of the other dicarboxylic acid to be substitutedmay be properly selected.

Preferable examples of the diol component becoming the raw material forthe amorphous polyester resin typically include ethylene glycol,diethylene glycol, triethylene glycol, cyclohexane dimethanol, and thelike. A part of the ethylene glycol may be substituted with the otherdiol component.

Examples of the other diol components include propylene glycol,trimethylene glycol, tetramethylene glycol, hexamethylene glycol,diethylene glycol, neopentyl glycol, polyalkylene glycol,1,4-cyclohexane dimethanol, glycerin, pentaerythritol, trimethylol,methoxy polyalkylene glycol, and the like.

The other diol components described above may be used alone or incombination of two or more. Moreover, the amount of the other diols tobe substituted may be properly selected.

Of the amorphous polyester resins under the present invention, thepolyethylene terephthalate formed by polycondensation of theterephthalic acid with the ethylene glycol is preferable in view ofcost. As described above, however, use of the copolymer polyestercontaining i) dicarboxylic acid component other than the terephthalicacid and/or ii) diol component other than the ethylene glycol is alsoeffective for accomplishing the object of the present invention.

Examples of the copolymer polyester include the one made of apolycondensation of i) a dicarboxylic acid component (60 mol % or morepart is terephthalic acid, and the remaining part is substituted withother dicarboxylic acid component) and ii) a diol component (60 mol % ormore part is ethylene glycol, and the remaining part is substituted withother diol component).

Moreover, the aromatic polyester resin usable under the presentinvention may be a mixture of polyethylene terephthalate and the abovecopolymer polyester. Use of the copolymer polyester is, however, in needof carefulness since selection, content and the like of thecopolymerization components may occasionally greatly change sheet'sglass transition temperature and tensile elasticity.

In the case of the above mixture, the aromatic polyester resin that issubstantially amorphous is preferred as a preferably used copolymerpolyester, which resin is prepared by substituting about 30 mol % ofethylene glycol (of polyethylene terephthalate) with 1,4-cyclohexanedimethanol, an example thereof including “PETG,” a brand of EASTMANCHEMICAL.

The polycarbonate resin in the polymer alloy resin composition of theabove polyester resin and the polycarbonate resin extensively signifiespolymers having carbonate bonding (—CO—O—) for a main chain thereof.

Examples of the polycarbonate resins include i) one manufactured frombisphenol A (which is synthesized by phenol and acetone) through aninterfacial polymerization, transesterification, a pyridine method andthe like, ii) polyester carbonate obtained by copolymerization ofbisphenol A and dicarboxylic acid derivative (for example, terephthalicacid (or isophthalic acid) dichloride and the like), and iii) oneobtained by polymerization of bisphenol A derivative (for example,tetramethyl bisphenol A and the like).

Having the required function as support, the support of the over sheetunder the present invention is not limited to a single-layer film, inother words, a multilayer body (two or more layers) constituted ofamorphous polyester resin film and other type of film is allowed.

For example, such a multilayer structure is allowed as has i) an innerlayer on a first side for the reversible thermosensitive recording layerand ii) an outer layer on a second side for heating-pressing (fusion)with the core sheet. In this structure, the resin constituting the outerlayer is preferred to have a melting temperature lower than that of theresin constituting the inner layer, so as to effectively improve thecard's heat resistance without losing low temperature fusibility.

More specifically, a double-layer sheet having the outer layer made ofpolyester resin and the inner layer made of polymer alloy resincomposition (amorphous polyester resin and polycarbonate resin) maybring about heat resistance, satisfy heat fusibility with the coresheet, and have excellent embossability.

Moreover, such a support film may be used as, when necessary, containsadditives such as colorant, lubricant, filler, impact improver and thelike. The support film, especially, blended with i) a plate-shapedfiller such as talc, and ii) a tensile-strength reducing polymer such aspolybutylene terephthalate can be preferably used for improvingembossability.

Thickness of the support constituting the over sheet depends onthickness of the information recording-displaying card to bemanufactured, in general, however, preferably in a range from 50 μm to200 μm, and more preferably in a range from 75 μm to 150 μm.

Hereinafter described is the core sheet used under the presentinvention.

The core sheet used under the present invention is defined as the onefor forming the information recording-displaying card by bonding theover sheet to the surface of the core sheet into a unity. Ordinarily,the core sheet is shaped into a rectangular plate, and is made of resin.The core sheet may be, when necessary, of multilayer structure.

The core sheet may encapsulate an information storing section. Amagnetic information storing section may be bonded to or embedded in asingle resin sheet; while an information storing section which is an ICchip, an antenna coil and the like may be mated in a gap formed in athick resin sheet, or may be sandwiched between a plurality of resinsheets.

The core sheet having the information storing section disposed in theabove manners may be complicated and require labor forces for disposingthe magnetic tape and the like or for positioning the IC chip and thelike. However, to the above operations, the conventional technology isapplicable which is used for the information recording card free fromthe image displaying section.

The core sheet under the present invention is preferred to havethickness in a range from 100 μm to 800 μm, more preferably in a rangefrom 200 μm to 600 μm.

The material for the core sheet under the present invention is preferredto be thermoplastic resin that is deformable by heating-pressing andshaped substantially into a sheet. It is important for the core sheet tohave fusibility with the support film of the over sheet by theheating-pressing. For obtaining high adhesion to the over sheet, thecore sheet is preferred to use a resin of the same (common) type as thatof the over sheet at least in its surface layer section contacting theover sheet. Examples of the above same (common) resin include amorphouspolyester resin, polycarbonate resin, and the like.

Preferable examples of the thermoplastic resins include amorphouspolyester resin, polycarbonate resin, and an alloy (of polycarbonateresin and amorphous polyester resin). Not limited to the above,general-purpose resins such as polyolefine resin, crystal polyesterresin, acrylic resin, ABS resin, AS resin, biodegradable resin and thelike are also usable.

An engineering plastic having a good heat resistance may also be used asthe core sheet material. Examples of the engineering plastics includepolyphenylene sulfide, polyetherimide, polyimide, poly ether etherketone, and the like. Films or sheets having, as main component thereof,the above material(s) (one type, or two or more types) can be preferablyused.

Not limited to the adhesion, for bringing about a plurality of functionssuch as heat resistance and the like, the core sheet is preferred to beof a multilayer structure (two layers or more). In this case, the coresheet having two or more layers can be prepared in advance, followed bypressing by overlapping with the over sheet. In this case, otherwise, aplurality of the prepared core sheets can be overlapped with the oversheet in heating-pressing for fusion.

Examples of forming three-layer core sheet may include the following i)and ii): i) 1. amorphous polyester resin, 2. polycarbonate resin, and 3.amorphous polyester resin; and ii) 1. amorphous polyester resin, 2.alloy of polycarbonate resin and amorphous polyester resin, and 3.amorphous polyester resin. The above amorphous polyester of the outerlayer can bring about a low-temperature adhesion, the above intermediatelayer, that is, the polycarbonate resin or the alloy of thepolycarbonate resin and the amorphous polyester resin can bring aboutheat residence.

Hereinabove, the amorphous polyester resin for the outer layer includesi) amorphous polyester resin alone or ii) an alloy product havingamorphous polyester resin as a main component thereof while theintermediate polycarbonate resin includes i) polycarbonate resin aloneor ii) an alloy product having polycarbonate resin as a main componentthereof Depending on the object, thickness of the outer layer and theintermediate layer can be arbitrarily determined.

The core sheet is preferred to be any one of being transparent,semi-transparent and opaque, otherwise, may be white or coloredchromatic. Depending on the application, the core sheet may be properlydesigned.

For making a semi-transparent film and an opaque film, an inorganicpigment or an organic pigment may be blended with the resin of the coresheet. For making a transparent film, a certain amount of pigment may beblended as long as the transparency is not damaged.

In the core sheet, various additives other than the above pigments maybe blended such as plasticizer, charge preventing agent, and the like.

The surface of the core sheet is preferred to be subjected to embossingand the like for degassing in a joining.

Under the present invention, the methods of manufacturing the support ofthe over sheet, and manufacturing the film of the core sheet are notspecifically limited, and therefore those conventionally known can beused.

For forming the support (of the over sheet) and the film (of the coresheet) each of which is of a single-layer structure, the resincomposition is to be subjected to an extrusion with a T-die. For formingthe support (of the over sheet) and the film (of the core sheet) atleast one of which is of a multilayer structure; i) the resincomposition of each layer is to be subjected to a coextrusion forlaminating, or ii) each layer is to be made into a sheet followed by thelaminating. In view of productivity as well as cost, however, thecoextrusion is preferred for forming the layer.

Specifically, in the case of the single layer, the resin composition isblended or, when necessary, is shaped into a pellet to be inputted intoa hopper of the T-die extruder. Then, the resin composition is melted ina range of temperature from 200° C. to 280° C., extruded, cooled with acooling roll and the like for solidification, to thereby form a sheet.

In the case of the multilayer, the resin composition of each layer isblended or, when necessary, is shaped into a pellet to be inputted intoone of the respective hoppers of the T-die extruder having a pluralityof T-dies coupled therewith. Then, the resin compositions are melted ina range of temperature from 200° C. to 280° C., co-extruded, rapidlycooled with a cooling roll and the like for solidification, to therebyform laminated sheets.

For causing a high adhesion to the bonded product of the over sheet withthe core sheet (pressing, laminating), at least the respective surfacelayers thereof contacting each other are preferred to be made of thesame kind of resin.

Thickness of the over sheet and the core sheet is to be determined basedon thickness of the card to be manufactured.

For manufacturing a card having thickness of 760 μm specified in JIS X6301, for example, the over sheet having thickness of 50 μm to 250 μmand the core sheet having thickness of 50 μm to 700 μm can be socombined that they can form a certain card thickness.

For accomplishing the certain thickness, a plurality of the core sheetsmay be used. In the case of the non-contact IC card encapsulatingtherein the IC chip or the antenna, the thickness of the core sheet maybe determined based on the size of the IC chip or the antenna.

In this case, the over sheet having thickness of 50 μm to 200 μm and thecore sheet having thickness of 50 μm to 400 μm are preferable.Especially, for the over sheet having thickness of 100 μm, combining twocore sheets each having thickness of 280 μm is preferred.

Hereinafter described is a method of producing the informationrecording-displaying card by bonding the over sheet to the core sheet,as described above.

The term “boding” under the present invention denotes unification, byusing adhesive, heating-pressing (for thermal fusion), and the like.

FIG. 1A and FIG. 1B show schematics of a state for manufacturing theinformation recording-displaying card by heating-pressing the over sheetand the core sheet, using two core sheets and an outer layer sheet.

An over sheet 10 is sequentially provided with a support 1, a barrierlayer 2 on the support 1, a reversible thermosensitive recording layer 3and a protective layer 4.

Two core sheets 5 are so disposed as to be sandwiched between the oversheet 10 and an outer layer sheet 6, then a surface side of theprotective layer 4 of the over sheet 10 and a surface side of the outerlayer sheet 6 are to be further sandwiched between pressing plates forheating-pressing, to thereby thermally fuse the thus sandwiched.

In this example, the outer layer sheet 6 and the two core sheets 5 areunited, thereby become part of the information recording-displayingcard. The information recording-displaying card under the presentinvention is, however, not limited to have the structure describedabove.

For example, in FIG. 1A and FIG. 1B, a sheet (referred to as inletsheet) having a non-contact IC chip provided with an antenna coil may besandwiched between the two core sheets 5, and the outer layer sheet 6 towhich a magnetic stripe layer is temporarily transferred in advance maybe used. With this, the heating-pressing is to be carried out like thatdescribed above, to thereby form an IC card layered body which isprovided with the IC chip.

The thus formed unit is subjected to a punching (using a punch and thelike) into a card configuration having a certain size, to therebyprepare the information recording-displaying card.

The heating-pressing includes a pressing method, a laminating method andthe like. The heating-pressing is, however, not limited to the above,and may be used differentiatedly with the sheet material and the like tobe used.

A large core sheet and an over sheet which has a certain area and isdisposed on the large core sheet may be subjected to theheating-pressing, otherwise, a tape-shaped core sheet and a tape-shapedover sheet may be rolled for unification to be subjected to theheating-pressing. In sum, the method of manufacturing the informationrecording-displaying under the present invention is not specificallylimited.

Having the fusibility to the core sheet by the heating-pressing, theouter layer sheet is not specifically limited. In this case, however,the outer layer sheet is ordinarily smaller in thickness than the coresheet, and may be made of the materials selected from those for thesupport constituting the over sheet. Moreover, the outer layer sheet mayhave the same material as that of the support constituting the oversheet.

For manufacturing, by the heating-fusing, the conventional informationrecording card that is free from the reversible thermosensitiverecording layer, the outer layer sheet is generally used. An outer layersheet under the present invention may be selected from the aboveconventional outer layer sheet.

The terms “over sheet” and the “core sheet” under the present inventiondenote respective positions in a state in which the core sheet issandwiched between the over sheet and the outer layer sheet. Theinformation recording-displaying card under the present invention mayomit the outer layer sheet, depending on the method, in other words, theinformation recording-displaying card under the present inventionincludes those free from the outer layer sheet.

Described hereinafter is a heating-pressing process.

A temperature in the heating-pressing (referred to as pressingtemperature) over the melting point of the developing agent may cause atexture fog (or background fog), therefore the above temperature ispreferred to be equal to or less than the melting point of thedeveloping agent.

The pressure in the heating-pressing (pressing pressure) too high maydecrease a matting tone of the card's surface thus causing gloss or maybreak the surface layer thus causing stick, which are problematical.

For forming the card without influencing the special property“reversible thermosensitivity,” the upper limit of the pressingtemperature is preferred to be 160° C. or less, more preferably 150° C.or less and especially preferably 140° C. or less. Pressing at thepressing temperature more than the melting point of the developing agentor at more than 160° C. may cause the texture fog (or background fog)attributable to the developing agent and the dye, or may causeyellowing, which are problematical.

On the other hand, a lower limit of the pressing temperature ispreferred to be 100° C. or more, especially preferably 120° C. or more.Less than 100° C. hereinabove is likely to cause an insufficient fusionthus leading to peeling, which is problematical.

An upper limit of the pressing pressure is preferred to be 40 kg/cm² orless, especially preferably 30 kg/cm² or less. More than 40 kg/cm²hereinabove may cause breakage of the base material or the IC chip,which is problematical.

On the other hand, a lower limit of the pressing pressure is preferredto be 5 kg/cm² or more, especially preferably 10 kg/cm² or more. Lessthan 5 kg/cm² hereinabove is likely to cause an insufficientpressing-adhesion thus leading to peeling, which is problematical.

The heating-pressing time is preferably 5 minutes to 20 minutes.

Preparing the information recording-displaying card having the “embossmarking” through the embossing can actively make use of the followingfeatures of the present invention.

More specifically about this: The over sheet under the present inventionis embossable. Therefore, in combining the over sheet with the coresheet which is also embossable, the over sheet and the core sheet mayhave substantially the same size with each other, which is advantageous.

With this, the over sheet may be bonded to substantially an entire faceof the core sheet. The thus prepared information recording-displayingcard can be embossable from an upper portion of the over sheet.Therefore, the image displaying section expressing a primary function ofthe over sheet and the “emboss marking” by the embossing can each have abroadened freedom in terms of sizing and positioning, which is anadvantage not expected from the conventional informationrecording-displaying card.

Moreover, the over sheet to be bonded may be smaller in size than thecore sheet. In this case, however, preparation of the over sheet havingdifferent size and bonding the over sheet to a certain position on thecore sheet are needed. In other words, positioning accuracy is neededfor the bonding, causing the shortcoming in the productivity as theconventional information recording-displaying card.

As long as the image displaying function is not influenced, the aboveinformation recording-displaying card having the over sheet whose areais small is, however, embossable without avoiding the over sheet or evenwith an interference with the over sheet. This feature of the presentinvention is an excellent advantage not found in the conventionalproduct, in terms of function and production of the informationrecording-displaying card itself.

As a matter of course, the information recording-displaying card underthe present invention may also allow the over sheet to be bonded to acertain position, like the conventional product, to thereby carry outthe embossing by avoiding the over sheet. Even in this case, theinformation recording-displaying card under the present invention canhave a high repetition durability, which is more advantageous than theconventional product.

In the reversible thermosensitive recording material which is the oversheet under the present invention, the heating temperature and/or thecooling rate after the heating can relatively form a coloring state anda decolorizing state. Hereinafter described is a basiccoloring-decolorizing phenomenon of a composition made of the coloringcoupler and the developing agent under the present invention.

FIG. 2 shows features of the recording medium including coloring densityrelative to a temperature. Increasing the temperature of the recordingmedium which is initially in a decolorizing state (A) may color therecording medium at a melt-starting temperature T₁, to thereby cause amelted coloring state (B). Rapidly quenching the recording medium fromthe melted coloring state (B) can reduce the recording medium to a roomtemperature with the recording medium kept in the coloring state, tothereby cause a solid coloring state (C). Whether or not this coloringstate is obtained depends on the rate of reducing the temperature fromthe melted state. Specifically, annealing (slow cooling) may cause thedecolorizing in the step of decreasing the temperature, thus forming i)the initial decolorizing state (A) or ii) a state in which the densityis relatively lower than the rapidly-quenched coloring state (C).

On the other hand, increasing the temperature again from therapidly-quenched coloring state (C) may cause the decolorizing at atemperature T₂ (from D to E) lower than the coloring temperature.Reducing the temperature from this point may return to the initialdecolorizing state (A). Being variable with the combination of thedeveloping agent and the coloring coupler, an actual coloringtemperature and an actual decolorizing temperature can be selectedaccording to the object. The density in the melted coloring state andthe density in the rapidly-quenched coloring state are not necessarilybe in concord with each other, but may differ from each other.

With the reversible thermosensitive recording material which is the oversheet under the present invention, the rapidly-quenched coloring state(C) obtained through the rapid quenching from the melted state is amixed state in which molecules of the developing agent and molecules ofthe coloring coupler can have a contact reaction with each other, whichstate is so often in a form of solid. This state may cohere thedeveloping agent with the coloring coupler, and thereby keeps thecoloring. Forming this cohesion structure can stabilize the coloring.

On the other hand, in the decolorizing state, a phase separation betweenthe developing agent and the coloring coupler is caused. Specifically,in the decolorizing state, the molecules of the compound of at least oneof the developing agent and the coloring agent may so gather as to forma domain or as to be crystallized, in other words, the cohering or thecrystallizing can separate the coloring coupler from the developingagent, thus causing a stable state. In many cases under the presentinvention, the coloring coupler and the developing agent may cause thephase separation from each other, with the developing agentcrystallized, to thereby cause a complete decolorizing. As is seen inFIG. 2, i) the decolorizing from the melted state by the annealing (slowcooling) and ii) the decolorizing from the coloring state by theincreased temperature may change the cohesion structure at thistemperature, causing the phase separation and the crystallization of thedeveloping agent.

For forming the coloring image on the reversible thermosensitiverecording material which is the over sheet under the present invention,the following steps 1) and 2) may be taken: 1) once heating, by using athermal head and the like, the reversible thermosensitive recordingmaterial to a temperature for melting-mixing, 2) then rapidly quenchingthe reversible thermosensitive recording material. The decolorizing canbe carried out by the following two: i) annealing (slow cooling) from aheated state, and ii) heating to a temperature slightly lower than thecoloring temperature. The above two, however, are substantially the samein that the coloring coupler and the developing agent cause the phaseseparation from each other and that at least one of the coloring couplerand the developing agent is temporarily kept at the crystallizingtemperature. The rapid quenching in forming the coloring state is forpreventing keeping of the phase separation temperature or of thecrystallizing temperature. Herein, the rapid quenching and the annealing(slow cooling) are relative to each other with respect to onecomposition, the boundary therebetween varying with the combination ofthe coloring coupler and the developing agent.

Hereinafter described is a technical matter, other than the supportdescribed above, of the reversible thermosensitive recording materialwhich is the over sheet under the present invention.

Disposing the reversible thermosensitive recording layer directly on thesupport is allowed. In this case, however, depending on the solventconstituting the coating solution for forming the reversiblethermosensitive recording layer, the support may be so eluted to bedeformed, be shrunk or be reduced in strength, thus damaging thefunction of the over sheet. In the above case, it is preferred to firstprovide the barrier layer on the support and then form the reversiblethermosensitive layer on the barrier layer.

Method of forming the barrier layer include i) coating a material thatis excellent in solvent resistance, and ii) laminating a film that isexcellent in solvent resistance.

Method 1. Coating Material Excellent in Solvent Resistance

The barrier layer is preferred to be made of a material havingresistance to a solvent of a coating solution for forming the reversiblethermosensitive recording layer.

In view of machinability, such a resin is preferred as is soluble ordispersible in an alcohol solvent, water and the like. The material forthe barrier layer is preferred to increase barring property againstorganic solvent when being set by heat, light and the like.

Specific examples of the barrier layer preferably include polyamideresin, polyvinyl alcohol resin, alcohol soluble phenol resin, polyesterresin, acrylic resin and the like.

Moreover, the examples of the useful materials for the barrier layerinclude i) polyurethane resin formed by crosslinking of acrylic polyol,polyester polyol and the like with isocyanate, ii) thermosetting resinsuch as epoxy resin and the like, iii) ultraviolet setting resin orelectron beam setting resin made by properly blending a material having,as main component thereof, oligomer (for example, urethane acrylate,epoxy acrylate and the like) with various acrylate monomers and otheradditives.

The above materials may be solved or dispersed in water, alcohol solventand the like.

Thickness of the barrier layer formed in the method 1 is preferably in arange from 0.1 μm to 10 μm.

Method 2. Laminating Film Excellent in Solvent Resistance

For allowing the barrier layer to have the solvent resistance, apolyester film crystallized can be used. The method of crystallizationinclude i) drawing the polyester film in the forming of the film, andii) heating the polyester film after forming an amorphous polyesterfilm. Generally used is the former method of drawing the polyester film,specifically, drawing PET film or drawing PEN film.

For improving adhesion of the barrier layer to the support and to therecording layer, it is preferable to apply an adhesive layer to asurface or a backface of the thus crystallized polyester film or tosubject the thus crystallized polyester film to a surface treatment witha corona discharge and the like.

Many of the barrier layers thus obtained have high solvent resistanceand high tensile strength. Thereby, thicker barrier layer may beinfluenced by the tensile strength, thereby decreasing theembossability. Therefore, the barrier layer is preferred to havethickness in a range from 1.0 μm to 8 μm, depending on the materialtherefor.

Stated below, for example, is a support using an amorphous polyestersheet having thickness of 100 μm, with a drawing PET film laminated. Inthis case, the storage elasticity of the drawing PET film at 180° C. ishigher than that of the amorphous polyester sheet. With this, the PETfilm having thickness of 38 μm which may have the storage elasticity of8.3 E+07 (8.3×10⁷) Pa at 180° C. is likely to cause a failure after theembossing.

On the other hand, thickness of 8 μm or thickness of 4.5 μm may bringabout, respectively, 4.9 E+07 (4.9×10⁷) Pa and 2.4 E+07 (2.4×10⁷) Pa,thus making the embossing easier.

Described below is the reversible thermosensitive recording layer of thereversible thermosensitive recording material.

The reversible thermosensitive recording layer is preferred to have filmthickness in a range from 1 μm to 20 μm, more preferably from 3 μm to 15μm.

Examples of the leuco dyes (electron-donating coloring compound) usedfor the reversible thermosensitive recording layer of the reversiblethermosensitive recording material are described below, but not limitedthereto. The leuco dyes described hereinafter may be used alone or incombination.

-   2-anilino-3-methyl-6-diethyl amino fluoran,    2-anilino-3-methyl-6-di(N-butyl amino)fluoran,    2-anilino-3-methyl-6-(N-n-propyl-N-methyl amino)fluoran,    2-anilino-3-methyl-6-(N-isopropyl-N-methyl amino)fluoran,    2-anilino-3-methyl-6-(N-isobutyl-N-methyl amino)fluoran,    2-anilino-3-methyl-6-(N-n-amyl-N-methyl amino)fluoran,    2-anilino-3-methyl-6-(N-sec-butyl-N-methyl amino)fluoran,    2-anilino-3-methyl-6-(N-n-amyl-N-ethyl amino)fluoran,    2-anilino-3-methyl-6-(N-iso-amyl-N-ethyl amino)fluoran,    2-anilino-3-methyl-6-(N-n-propyl-N-isopropyl amino)fluoran,    2-anilino-3-methyl-6-(N-cyclohexyl-N-methyl amino)fluoran,-   2-anilino-3-methyl-6-(N-ethyl-p-toluidino)fluoran,    2-anilino-3-methyl-6-(N-methyl-p-toluidino)fluoran, 2-(m-trichloro    methyl anilino)-3-methyl-6-diethyl amino fluoran, 2-(m-trifluoro    methyl anilino)-3-methyl-6-diethyl amino fluoran, 2-(m-trichloro    methyl anilino)-3-methyl-6-(N-cyclohexyl-N-methyl amino)fluoran,    2-(2,4-dimethyl anilino)-3-methyl-6-diethyl amino fluoran,    2-(N-ethyl-p-toluidino)-3-methyl-6-(N-ethyl anilino)fluoran,    2-(N-ethyl-p-toluidino)-3-methyl-6-(N-propyl-p-toluidino)fluoran,    2-anilino-6-(N-n-hexyl-N-ethyl amino)fluoran, 2-(o-chloro    anilino)-6-diethyl amino fluoran, 2-(o-chloro anilino)-6-dibutyl    amino fluoran, 2-(m-trifluoro methyl anilino)-6-diethyl amino    fluoran, 2,3-dimethyl-6-dimethor amino fluoran,-   3-methyl-6-(N-ethyl-p-toluidino)fluoran, 2-chloro-6-diethyl amino    fluoran, 2-bromo-6-diethyl amino fluoran, 2-chloro-6-dipropyl amino    fluoran, 3-chloro-6-cyclohexyl amino fluoran, 3-bromo-6-cyclohexyl    amino fluoran, 2-chloro-6-(N-ethyl-N-isoamyl amino)fluoran,    2-chloro-3-methyl-6-diethyl amino fluoran,    2-anilino-3-chloro-6-diethyl amino fluoran, 2-(o-chloro    anilino)-3-chloro-6-cyclohexyl amino fluoran, 2-(m-trifluoro methyl    anilino)-3-chloro-6-diethyl amino fluoran, 2-(2,3-dichloro    anilino)-3-chloro-6-diethyl amino fluoran, 1,2-benzo-6-diethyl amino    fluoran, 3-diethyl amino-6-(m-trifluoro methyl anilino)fluoran,    3-(1-ethyl-2-methyl indole-3-yl)-3-(2-ethoxy-4-diethyl amino    phenyl)-4-azaphthalide, 3-(1-ethyl-2-methyl    indole-3-yl)-3-(2-ethoxy-4-diethyl amino phenyl)-7-azaphthalide,    3-(1-octyl-2-methyl indole-3-yl)-3-(2-ethoxy-4-diethyl amino    phenyl)-4-azaphthalide, 3-(1-ethyl-2-methyl    indole-3-yl)-3-(2-methyl-4-diethyl amino phenyl)-4-azaphthalide,    3-(1-ethyl-2-methyl indole-3-yl)-3-(2-methyl-4-diethyl amino    phenyl)-7-azaphthalide, 3-(1-ethyl-2-methyl    indole-3-yl)-3-(4-diethyl amino phenyl)-4-azaphthalide,    3-(1-ethyl-2-methyl indole-3-yl)-3-(4-N-n-amyl-N-methyl amino    phenyl)-4-azaphthalide, 3-(1-methyl-2-methyl    indole-3-yl)-3-(2-hexyloxy-4-diethyl amino phenyl)-4-azaphthalide,    3,3-bis(2-ethoxy-4-diethyl amino phenyl)-4-azaphthalide,    3,3-bis(2-ethoxy-4-diethyl amino phenyl)-7-azaphthalide.

Other than the fluoran compounds and the azaphthalide compoundsdescribed above, the conventional leuco dye can be used alone or incombination, as the coloring coupler under the present invention.Examples of the other coloring couplers are described below.

-   2-(p-acetyl anilino)-6-(N-n-amyl-N-n-butyl amino)fluoran, 2-benzil    amino-6-(N-ethyl-p-toluidino)fluoran, 2-benzil    amino-6-(N-methyl-2,4-dimethyl anilino)fluoran, 2-benzil    amino-6-(N-ethyl-2,4-dimethyl anilino)fluoran, 2-benzil    amino-6-(N-methyl-p-toluidino)fluoran, 2-benzil    amino-6-(N-ethyl-p-toluidino)fluoran, 2-(di-p-methyl benzil    amino)-6-(N-ethyl-p-toluidino)fluoran, 2-(α-phenylethyl    amino)-6-(N-ethyl-p-toluidino)fluoran, 2-methyl amino-6-(N-methyl    anilino) fluoran, 2-methyl amino-6-(N-ethyl anilino)fluoran,    2-methyl amino-6-(N-propyl anilino)fluoran,-   2-ethyl amino-6-(N-methyl-p-toluidino)fluoran, 2-methyl    amino-6-(N-methyl-2,4-dimethyl anilino)fluoran, 2-ethyl    amino-6-(N-ethyl-2,4-dimethyl anilino)fluoran, 2-dimethyl    amino-6-(N-methyl anilino)fluoran, 2-dimethyl amino-6-(N-ethyl    anilino) fluoran, 2-diethyl amino-6-(N-methyl-p-toluidino)fluoran,    2-diethyl amino-6-(N-ethyl-p-toluidino)fluoran, 2-dipropyl    amino-6-(N-methyl anilino) fluoran, 2-dipropyl amino-6-(N-ethyl    anilino)fluoran, 2-amino-6-(N-methyl anilino)fluoran,    2-amino-6-(N-ethyl anilino)fluoran, 2-amino-6-(N-propyl    anilino)fluoran, 2-amino-6-(N-methyl-p-toluidino)fluoran,    2-amino-6-(N-ethyl-p-toluidino)fluoran,    2-amino-6-(N-propyl-p-toluidino) fluoran,    2-amino-6-(N-methyl-p-ethyl anilino)fluoran,    2-amino-6-(N-ethyl-p-ethyl anilino)fluoran,    2-amino-6-(N-propyl-p-ethyl anilino)fluoran,    2-amino-6-(N-methyl-2,4-dimethyl anilino)fluoran,    2-amino-6-(N-ethyl-2,4-dimethyl anilino)fluoran,    2-amino-6-(N-propyl-2,4-dimethyl anilino)fluoran,    2-amino-6-(N-methyl-p-chloro anilino)fluoran,    2-amino-6-(N-ethyl-p-chloro anilino)fluoran,    2-amino-6-(N-propyl-p-chloro anilino)fluoran,    1,2-benzo-6-(N-ethyl-N-isoamyl amino)fluoran, 1,2-benzo-6-dibutyl    amino fluoran, 1,2-benzo-6-(N-methyl-N-cyclohexyl amino)fluoran,    1,2-benzo-6-(N-ethyl-N-toluidino)fluoran, and the like.

Specific examples of the other coloring couplers preferably used underthe present invention are described below.

-   2-anilino-3-methyl-6-(N-2-ethoxy propyl-N-ethyl amino)fluoran,    2-(p-chloro anilino)-6-(N-n-octyl amino)fluoran, 2-(p-chloro    anilino)-6-(N-n-palmityl amino)fluoran, 2-(p-chloro    anilino)-6-(di-N-octyl amino)fluoran, 2-benzoyl    amino-6-(N-ethyl-p-toluidino)fluoran, 2-(o-methoxy benzoyl    amino)-6-(N-methyl-p-toluidino)fluoran, 2-dibenzil    amino-4-methyl-6-diethyl amino fluoran, 2-dibenzil    amino-4-methoxy-6-(N-methyl-p-toluidino)fluoran, 2-dibenzil    amino-4-methyl-6-(N-ethyl-p-toluidino)fluoran, 2-(α-phenylethyl    amino)-4-methyl-6-diethyl amino fluoran,    2-(p-toluidino)-3-(t-butyl)-6-(N-methyl-p-toluidino)fluoran,    2-(o-methoxy carbonyl amino)-6-diethyl amino fluoran, 2-acetyl    amino-6-(N-methyl-p-toluidino)fluoran,    4-methoxy-6-(N-ethyl-p-toluidino) fluoran, 2-ethoxy ethyl    amino-3-chloro-6-dibutyl amino fluoran, 2-dibenzil    amino-4-chloro-6-(N-ethyl-p-toluidino)fluoran, 2-(α-phenylethyl    amino)-4-chloro-6-diethyl amino fluoran, 2-(N-benzil-p-trifluoro    methyl anilino)-4-chloro-6-diethyl amino fluoran,    2-anilino-3-methyl-6-pyrrolidino fluoran,    2-anilino-3-chloro-6-pyrrolidino fluoran,    2-anilino-3-methyl-6-(N-ethyl-N-tetrahydro furfuryl amino)fluoran,    2-mesidino-4′,5′-benzo-6-diethyl amino fluoran, 2-(m-trifluoro    methyl anilino)-3-methyl-6-pyrrolidino fluoran, 2-(α-naphthyl    amino)-3,4-benzo-4′-bromo-6-(N-benzil-N-cyclohexyl amino)fluoran,    2-piperidino-6-diethyl amino fluoran, 2-(N-n-propyl-p-trifluoro    methyl anilino)-6-morpholino fluoran, 2-(di-N-p-chloro phenyl-methyl    amino)-6-pyrrolidino fluoran, 2-(N-n-propyl-m-trifluoro methyl    anilino)-6-morpholino fluoran, 1,2-benzo-6-(N-ethyl-N-n-octyl    amino)fluoran, 1,2-benzo-6-diallyl amino fluoran,    1,2-benzo-6-(N-ethoxy ethyl-N-ethyl amino)fluoran,-   benzoleuko methylene blue, 2-[3,6-bis(diethyl amino)-7-(o-chloro    anilino) xanthyl]benzoic acid lactam, 2-[3,6-diethyl    amino)-9-(o-chloro anilino) xanthyl]benzoic acid lactam,    3,3-bis(p-dimethyl amino phenyl)-phthalide, 3,3-bis(p-dimethyl amino    phenyl)-6-dimethyl amino phthalide (otherwise, referred to as    crystal violet lactone), 3,3-bis-(p-dimethyl amino phenyl)-6-diethyl    amino phthalide, 3,3-bis-(p-dimethyl amino phenyl)-6-chloro    phthalide, 3,3-bis-(p-dibutyl amino phenyl) phthalide,    3-(2-methoxy-4-dimethyl amino phenyl)-3-(2-hydroxy-4,5-dichloro    phenyl) phthalide, 3-(2-hydroxy-4-dimethyl amino    phenyl)-3-(2-methoxy-5-chloro phenyl) phthalide,    3-(2-hydroxy-4-dimethoxy amino phenyl)-3-(2-methoxy-5-chloro phenyl)    phthalide, 3-(2-hydroxy-4-dimethyl amino    phenyl)-3-(2-methoxy-5-nitro phenyl) phthalide,    3-(2-hydroxy-4-diethyl amino phenyl)-3-(2-methoxy-5-methyl phenyl)    phthalide, 3-(2-methoxy-4-dimethyl amino    phenyl)-3-(2-hydroxy-4-chloro-5-methoxy phenyl) phthalide,    3,6-bis(dimethyl amino)fluorene spiro(9,3′)-6′-dimethyl amino    phthalide, 6′-chloro-8′-methoxy-benzo indolino-spiropyran,    6′-bromo-2′-methoxy-benzo indolino-spiropyran, and the like.

Hereinafter described is the developing agent (electron-acceptingcompound) used in combination with the coloring coupler.

JP-A No. 5-124360 described above discloses a typical example of anorganic phosphoric acid, an aliphatic carboxylic acid compound or aphenol compound which have a long-chain aliphatic hydrocarbon radical.In addition, JP-A No. 5-124360 discloses a compound having incombination i) a structure having developability of coloring thecoloring coupler in the molecule and ii) a structure of controllingcohesive force between the molecules. Examples of the structure havingthe developability include phenol hydroxyl group, carboxyl group,phosphoric acid group and the like, but not limited thereto, as long asa group that is capable of coloring the coloring coupler is included.Specifically, the above groups may include a thiocarbamide group, acarboxylic metal group, and the like.

A typical example of the structure controlling the cohesive forcebetween molecules include hydrocarbon radical such as a long-chain alkylgroup and the like. Preferably, the hydrocarbon radical may have 8 ormore carbon atoms, so as to obtain a good coloring property and a gooddecolorizing property. The hydrocarbon radical may contain anunsaturated bond or may encapsulate a branched hydrocarbon radical. Inthis case, the main chain portion is preferred to have 8 or more carbonatoms. The developing agent as described above has a structure in whichthe structure having developability is bonded with a structurecontrolling the cohesive force between the molecules (namely, astructure such as hydrocarbon radical). To the above bonding portion, abivalent group including hetero atom, or a combination of a plurality ofthe bivalent groups may be sandwichedly bonded.

Hereinafter described are specific examples of the developing agent usedunder the present invention. The developing agent may be used alone orin combination of two or more.

In the above formula, X₁ denotes a bivalent group including hetero atom,or a direct bonding hand. X₂ denotes a bivalent group including heteroatom. R₁ denotes a bivalent hydrocarbon radical. R₂ denotes ahydrocarbon radical having 1 to 22 carbon atoms. p denotes an integerfrom 0 to 4. The R₁ and the X₂ which are repeated when p is 2 to 4 maybe the same or different. q denotes 1 to 3.

Specifically, R₁ and R₂ denote a hydrocarbon radical which is allowed tohave a substitutional group. R₁ and R₂ may be i) an aliphatichydrocarbon radical, ii) an aromatic hydrocarbon radical, and iii) acombination of the aliphatic hydrocarbon radical and the aromatichydrocarbon radical. The aliphatic hydrocarbon radical may be a straightchain or a branched chain, or may have an unsaturated bond. Thesubstitutional group adhering to the hydrocarbon radical includehydroxyl group, halogen, alkoxy group and the like. R₁ may be a directbonding hand.

Sum of the carbon atom(s) of R₁ and the carbon atom(s) of R₂ ispreferred to be 8 or more, more preferably 11 or more, since 7 or lesshereinabove may decrease coloring stability and decolorizing property.Each of X₁ and X₂ denotes a bivalent group including hetero atom,preferably denotes a bivalent group having at least one group expressedby the formulas 1.

Specific examples of X₁ and X₂ are described in the formulas 2.

Hereinafter described in the following formulas 3 are specific examplesof the phenol compounds under the present invention. The presentinvention is, however, not limited thereto. The phenol compounds may beused alone or in combination.

Examples of the developing agent of organic phosphoric acid include thefollowing compounds. Dodecyl phosphonic acid, tetradecyl phosphonicacid, hexadecyl phosphonic acid, octadecyl phosphonic acid, eicosylphosphonic acid, docosyl phosphonic acid, tetracosyl phosphonic acid,ditetradecyl ester phosphate, dihexadecyl ester phosphate, dioctadecylester phosphate, dieicosyl ester phosphate, and dibehenyl ester(Behenyl) phosphate, and the like.

Examples of the aliphatic carboxyl compounds include the following.2-hydroxy tetradecanoic acid, 2-hydroxy hexadecanoic acid, 2-hydroxyoctadecanoic acid, 2-hydroxy eicosane acid, 2-hydroxy docosane acid,2-bromo hexadecanoic acid, 2-bromo octa decanoic acid, 2-bromo eicosaneacid, 2-bromo docosane acid, 3-bromo docosane acid, 2,3-dibromooctadecanoic acid, 2-fluoro decanoic acid, 2-fluoro tetradecanoic acid,2-fluoro hexadecanoic acid, 2-fluoro octa decanoic acid, 2-fluoroeicosane acid, 2-fluoro docosane acid, 2-iodohexa decanoic acid,2-iodoocta decanoic acid, 3-iodohexa decanoic acid, 3-iodoocta decanoicacid, perfluoro octa decanoic acid, and the like.

Examples of aliphatic dicarboxylic acid compounds and tricarboxylic acidcompounds are described below. 2-dodecyl oxysuccinic acid, 2-tetradecyloxysuccinic acid, 2-hexadecyl oxysuccinic acid, 2-octadecyl oxysuccinicacid, 2-eicosyl oxysuccinic acid, 2-dodecyl oxysuccinic acid, 2-dodecylthio succinic acid, 2-tetradecyl thio succinic acid, 2-hexadecyl thiosuccinic acid, 2-octadecyl thio succinic acid, 2-eicosyl thio succinicacid, 2-docosyl thio succinic acid, 2-tetracosyl thio succinic acid,2-hexadecyl dithio succinic acid, 2-octadecyl dithio succinic acid,2-eicosyl dithio succinic acid, dodecyl succinic acid, tetradecylsuccinic acid, pentadecyl succinic acid, hexadecyl succinic acid,octadecyl succinic acid, eicosyl succinic acid, docosyl succinic acid,2,3-dihexadecyl succinic acid, 2,3-dioctadecyl succinic acid,2-methyl-3-hexadecyl succinic acid, 2-methyl-3-octadecyl succinic acid,2-octadecyl-3-hexadecyl succinic acid, hexadecyl malonic acid, octadecylmalonic acid, eicosyl malonic acid, docosyl malonic acid, dihexadecylmalonic acid, dioctadecyl malonic acid, didocosyl malonic acid, methyloctadecyl malonic acid, 2-hexadecyl glutaric acid, 2-octadecyl glutaricacid, 2-eicosyl glutaric acid, docosyl glutaric acid, 2-pentadecyladipic acid, 2-octadecyl adipic acid, 2-eicosyl adipic acid, 2-docosyladipic acid, 2-hexa decanoyl oxypropane-1,2,3-tricarboxylic acid, 2-octadecanoyl oxypropane-1,2,3-tricarboxylic acid, and the like.

A proper ratio of the coloring coupler relative to the developing agentmay vary with the combination of the compounds to be used, in general,mole ratio is 1 coloring coupler relative to 0.1 to 20 developing agent,preferably 0.2 to 10 developing agent. The developing agent out of theabove range (more than or less than) may decrease density of thecoloring state, which is problematical. Ratio of a decolorizing promoteris preferably 0.1 weight % to 300 weight % relative to the developingagent, more preferably 3 weight % to 100 weight %. The coloring couplerand the developing agent may be used encapsulated in a microcapsule. Inthe recording layer, ratio of the coloring component relative to theresin is 1 (coloring component) to 0.1 (resin) to 10 (resin). This ratioless than the above may shorten the heat strength of the recordinglayer, while the ratio more than the above may decrease the coloringdensity occasionally, which are problematical.

The reversible thermosensitive recording layer constituting thereversible thermosensitive recording material under the presentinvention may ordinarily contain the resin.

Specific examples of the resins contained in the reversiblethermosensitive recording layer include i) resins having a groupreactive with crosslinking agent such as acrylic polyol resin, polyesterpolyol resin, polyurethane polyol resin, phenoxy resin, polyvinylbutyral resin, cellulose acetate propionate, cellulose acetate butyrateand the like, ii) a resin which is a copolymerization of a first monomer(having a group reactive with crosslinking agent) and a second monomerother than the first monomer. The present invention is, however, notlimited to the above compounds.

Moreover, the above resins may be subjected to a block copolymerizationor a graft copolymerization with a benzotriazol ultraviolet absorbentbone or a cyclohexane bonding bone.

The reversible thermosensitive recording material which is the oversheet under the present invention, when necessary, may use an additivefor improving and controlling coating property, coloring property, anddecolorizing property of the thermosensitive recording layer. Examplesof the above additive include surfactant, conductive agent, filler,oxidation inhibitor, light stabilizer, coloring stabilizer, decolorizingpromoter, and the like. Preferable examples of the decolorizing promoterinclude i) a compound having a bivalent group (containing hetero atom)and an alkyl chain (having 8 or more carbon atoms), ii) a compoundhaving N,N′-2 substitutional group, iii) and the like. The presentinvention is, however, not limited to the above compounds.

Under the present invention, the reversible thermosensitive recordinglayer may contain a curing agent.

Examples of the curing agent used herein include modified bodies knownin the art such as urethane modified body of isocyanate monomer,allophanate modified body, isocyanurate modified body, bullet modifiedbody, carbodiimide modified body, block doisocyanate, and the like.Examples of the isocyanate monomer forming the modified body includetolylenediisocyanate (TDI), 4,4′-diphenyl methane isocyanate (MDI),xylene diisocyanate (XDI), naphthalene diisocyanate (NDI), paraphenylenediisocyanate (PPDI), tetramethyl xylene diisocyanate (TMXDI),hexamethylene diisocyanate (HDI), dicyclo hexyl methane diisocyanate(HMDI), isophorone diisocyanate (IPDI), lysine diisocyanate (LDI),isopropylidene bis(4-cyclohexyl isocyanate) (IPC), cyclohexyldiisocyanate (CHDI), tolidine diisocyanate (TODI), and the like. Thepresent invention is, however, not limited to the above compounds.

Moreover, the reversible thermosensitive recording layer may contain acuring agent of crosslinking promoter.

Examples of the crosslinking promoter include tertiary amines such as1,4-diaza-bicyclo [2, 2, 2] octane, metal compound such as organic tincompound, and the like. The curing agent added may cause crosslinkingreaction entirely or not entirely. In other words, unreacted curingagent is allowed.

The crosslinking reaction of the above may proceed according to the timeelapsed. The above unreacted curing agent, therefore, does notnecessarily signify that the crosslinking reaction is not proceeding atall. Instead, sensing the unreacted curing agent suggests that a resinin the crosslinking state is present. For distinguishing whether thepolymer under the present invention is in the crosslinking state or anon-crosslinking state, submerging the coat film in the highly-solublesolvent is proposed.

More specifically, a polymer in the non-crosslinking state may become aneluate in the solvent, and thereby does not remain in a solute. Withthis, analyzing the polymer structure of the solute is recommended forthe above distinction. Failure in verifying the polymer structure in thesolute may indicate that the polymer is in the non-crosslinking state,distinguishing from the polymer in the crosslinking state.

When other layer(s) is laminated, a layer structure and a film thicknessthereof are to be verified by a cross sectional photograph taken by TEM(transmission electron microscope), SEM (scanning electron microscope)and the like. Then, an irrelevant layer(s) is to be removed at all, tothereby expose a target layer. Then, the thus exposed layer is to betaken (shaved), to be followed by the measurement according to the abovemethod.

Formation of the recording layer may use a coating solution which isprepared by evenly mixing-dispersing a mixture made of the developingagent, the coloring coupler, the various additives, the curing agent,the resin in crosslinking state, and the coating solvent which aredescribed above.

Specific examples of the solvent used for preparing the coating solutioninclude water; alcohols such as methanol, ethanol, isopropanol,n-butanol, methyl isocarbinol; ketones such as acetone, 2-butanone,ethyl amyl ketone, diacetone alcohol, isophorone, cyclohexanone, and thelike; amides such as N,N-dimethyl formamide, N,N-dimethyl acetamide, andthe like; ethers such as diethyl ether, isopropyl ether,tetrahydrofuran, 1,4-dioxane, 3,4-dihydro-2H-pyran, and the like; glycolethers such as 2-methoxy ethanol, 2-ethoxy ethanol, 2-butoxy ethanol,ethylene glycol dimethyl ether, and the like; glycol ether acetates suchas 2-methoxy ethyl acetate, 2-ethoxy ethyl acetate, 2-butoxy ethylacetate, and the like; esters such as methyl acetate, ethyl acetate,isobutyl acetate, amyl acetate, ethyl lactate, ethylene carbonate, andthe like; aromatic hydrocarbons such as benzene, toluene, xylene, andthe like; aliphatic hydrocarbons such as hexane, heptane, iso-octane,cyclohexane, and the like; halogenated hydrocarbons such as methylenechloride, 1,2-dichloro ethane, dichloro propane, chloro benzene, and thelike; sulfoxides such as dimethyl sulfoxide, and the like; pyrrolidonesuch as N-octyl-2-pyrrolidone; and the like.

Preparing the coating solution can be carried out by using known coatingsolution-dispersing unit such as paint shaker, ball mill, attritor,three-roll mill, sand mill, dynomill, colloid mill and the like.Dispersing each material in the solvent by using the above coatingsolution-dispersing unit is allowed, or dispersing each material alonein the solvent and mixing is also allowed. Moreover, heating-dissolving,followed by a rapid quenching or an annealing (slow cooling), andfollowed by depositing is allowed.

The coating method for forming the recording layer is not specificallylimited, examples thereof including those known in the art such as bladecoating, wire bar coating, spray coating, air knife coating, beadcoating, curtain coating, gravure coating, kiss coating, reverse rollcoating, dip coating, die coating, and the like.

After coating-drying of the recording layer, a curing treatment of therecording layer is to be carried out, when necessary. In this case,carrying out a heat treatment using a high temperature vessel and thelike at a relatively high temperature for a short time is allowed, orcarrying out the heat treatment at a relatively low temperature for along time is also allowed. Specifically, the crosslinking reaction hasthe following preferable conditions in view of reactivity: 30° C. to130° C. for 1 minutes to 150 hours, more preferably 40° C. to 100° C.for 2 minutes to 120 hours. Since productivity is esteemed inmanufacturing, spending time until the crosslinking is sufficientlycompleted is of difficulty. The crosslinking step is, therefore, allowedto be provided apart from the drying step. The crosslinking step ispreferred to have conditions of 40° C. to 100° C. for 2 minutes to 120hours for heating.

Described next is the protective layer which can be arbitrarily providedon the reversible thermosensitive recording layer, for ordinarilypreventing sticking and for improving durability.

The protective layer preferably has a thickness in a range from 0.1 μmto 20 μm, more preferably 0.3 μm to 10 μm.

The protective layer may contain an inorganic ultraviolet absorbent oran organic ultraviolet absorbent, for the purpose of preventing thetexture fog (or background fog), content thereof being in a range from0.5 weight parts to 50 weight parts relative to 100 weight parts of abinder.

Known methods and the like used for the above recording layer can beused for the protective layer, such as the solvent of the coatingsolution, the dispersing unit of the coating solution, the binder, thecoating method, the drying-curing method, and the like.

Examples of the organic ultraviolet absorbents include:

-   i) benzo triazole ultraviolet absorbents such as    2-(2′-hydroxy-5′-methyl phenyl) benzo triazole,    2-(2′-hydroxy-5′-t-butyl phenyl) benzo triazole,    2-(2′-hydroxy-5′-t-butyl phenyl) benzo triazole,    2-(2′-hydroxy-3′,5′-di-t-butyl phenyl) benzo triazole,    2-(2′-hydroxy-3′-t-butyl-5′ octoxy phenyl) benzo triazole,    2-(2′-hydroxy-3′,5′-di-t-butyl phenyl)-5-chloro benzo triazole,    2-(2′-hydroxy-3′-t-butyl-5′-methyl phenyl)-5-chloro benzo triazole,    2-(2′-hydroxy-5′-ethoxy phenyl) benzo triazole, and the like;-   ii) benzo phenon ultraviolet absorbents such as 2,4-dihydroxy benzo    phenon, 2-hydroxy-4-methoxy benzo phenon, 2-hydroxy-4-n-octoxy benzo    phenon, 2-hydroxy-4-dodecyl oxy benzo phenon,    2,2′-dihydroxy-4-methoxy benzo phenon, 2,2′-dihydroxy-4,4′-dimethoxy    benzo phenon, 2,2′,4,4′-tetrahydroxy benzo phenon,    2-hydroxy-4-methoxy-2′-carboxy benzo phenon, 2-hydroxy-4-oxybenzil    benzo phenon, 2-hydroxy-4-chloro benzo phenon, 2-hydroxy-4-methoxy    benzo phenon-5-sulfonic acid, 2-hydroxy-4-methoxy benzo    phenon-5-sodium sulfonate, 2,2′-dihydorxy-4,4′-dimethoxy benzo    phenon-sodium sulfonate, and the like;-   iii) salicylic acid ester ultraviolet absorbents such as phenyl    salicylate, p-octyl phenyl salicylate, p-t-butyl phenyl salicylate,    carboxy phenyl salicylate, methyl phenyl salicylate, dodecyl phenyl    salicylate, 2-ethyl hexyl phenyl salicylate, homomenthyl phenyl    salicylate, and the like;-   iv) cyano acrylate ultraviolet absorbents such as 2-ethyl    hexyl-2-cyano-3,3′ diphenyl acrylate, ethyl-2-cyano-3,3′-diphenyl    acrylate, and the like;-   v) p-amino benzoic acid absorbents such as p-amino benzoic acid,    p-amino glyceryl benzoate, p-dimethyl amino amyl benzoate,    p-dihydroxy propyl ethyl benzoate, and the like;-   vi) cinnamic acid ultraviolet absorbents such as p-methoxy cinnamic    acid-2-ethyl hexyl, p-methoxy cinnamic acid-2-ethoxy ethyl, and the    like;-   4-t-butyl-4-methoxy-dibenzoyl methane;-   urocanic acid;-   urocanic acid ethyl; and the like.

Examples of the inorganic ultraviolet absorbents include zinc sulphide,titanium oxide, cerium oxide, tin oxide, molybdenum oxide, zinc oxide,barium oxide, silica, alumina, antimony oxide, magnesium oxide,zirconium oxide, barium oxide, calcium oxide, strontium oxide, siliconenitride, aluminum nitride, boron nitride, barium nitride, and the like.

For preventing sticking or improving durability of the protective layer,other fillers free from the ultraviolet absorbing property or theultraviolet shutting property may be added to the protective layer, thefillers being divided into an inorganic filler and an organic filler.

Examples of the inorganic fillers include calcium carbonate, magnesiumcarbonate, silicic anhydride, hydrated silica, hydrated aluminumsilicate, hydrated calcium silicate, alumina, iron oxide, calcium oxide,magnesium oxide, chromium oxide, manganese oxide, silica, talc, mica,and the like.

Examples of the organic fillers include silicone resin; cellulose resin;epoxy resin; nylon resin; phenol resin; polyurethane resin; urea resin;melamine resin; polyester resin; polycarbonate resin; styrene resinssuch as styrene, polystyrene, polystyrene-isoprene, styrene vinylbenzene, and the like; acrylic resins such as acrylic vinylidenechloride, acrylic urethane, acrylic ethylene, and the like; polyethyleneresin; formaldehyde resins such as benzoguanamine formaldehyde, melamineformaldehyde, and the like; polymethyl methacrylate resin; vinylchloride resin; and the like. Under the present invention, the fillersmay be used alone or in combination of two or more. In the case of theplurality of the fillers, the combination of the inorganic filler andthe organic filler is not specifically limited. Configuration thereofmay include sphere, grain, plate, needle, and the like. Content of thefiller in the protective layer is 5 volume % to 50 volume %.

For preventing fusion to the thermal head, the protective layer may beadded by a lubricant, specific examples thereof including syntheticwaxes such as ester wax, paraffin wax, polyethylene wax, and the like;plant wax such as cured castor oil and the like; animal wax such as beeftallow cured oil and the like; higher alcohols such as stearyl alcohol,behenyl alcohol, and the like; higher fatty acids such as margaric acid,lauric acid, myristic acid, palmitic acid, stearic acid, behenic acid;higher fatty acid esters such as sorbitan fatty acid ester; amides suchas stearamide, oleamide, amide laurate, ethylene bis stearamide,methylene bis stearamide, methylol stearamide, and the like; and thelike. Content of the lubricant in the protective layer is 0.1 volume %to 95 volume %, more preferably 1 volume % to 75 volume %.

The reversible thermosensitive recording material used as the over sheetunder the present invention may be provided with an intermediate layerbetween the recording layer and the protective layer, for the purpose ofi) improving adhesion between the recording layer and the protectivelayer, ii) preventing the recording layer from causing degenerationattributable to application of the protective layer, iii) preventing theadditive in the protective layer from moving to the recording layer, andiv) preventing the additive in the recording layer from moving to theprotective layer.

Preferably, the intermediate layer has a thickness in a range from 0.1μm to 20 μm, more preferably 0.3 μm to 10 μm. Known methods and the likeused for the above recording layer can be used for the intermediatelayer, such as the solvent, the dispersing unit of the coating solution,the binder, the coating method, the drying-curing method, and the like.

The intermediate layer may contain an inorganic ultraviolet absorbent oran organic ultraviolet absorbent (which are used for the aboveprotective layer), for the purpose of preventing the texture fog (orbackground fog), content thereof being in a range from 0.5 weight partsto 50 weight parts relative to 100 weight parts of the binder.

Moreover, the reversible thermosensitive recording material for theinformation recording-displaying card under the present invention mayallow the reversible thermosensitive recording layer to contain aphotothermal transducer substance; or may be provided, adjacent to therecording layer, with a layer containing the photothermal transducersubstance (referred to as photothermal transducer layer).

Making the above structure containing the photothermal transducersubstance can carry out the recording (coloring and decolorizing) evenwhen a low-output semiconductor laser and the like are used.

Of the above two methods using the photothermal transducer substance,providing the photothermal transducer layer adjacent to the reversiblethermosensitive recording layer is more preferable in view of cost(i.e., photothermal transducer substance is costly) and less influenceon the material constituting the recording layer.

Moreover, under the present invention, an ultraviolet absorbent layerhaving a visible-light transparency can be provided so as to protect thelayer containing the photothermal transducer substance.

Examples of the photothermal transducer substance include an infraredabsorbent pigment, carbon black and the like, which have an absorptionpeak in the vicinity of oscillating wavelength of a semiconductor laserbeam to be used.

In general, the semiconductor laser to be used has wavelength range from100 nm to 1000 nm, more preferably 700 nm to 900 nm, and the infraredabsorbent pigment preferably has the peak absorption wavelength in theabove range. Examples of the above pigment include cyanine pigment,polymethine pigment, anthraquinone pigment, and the like. Of the abovepigments, the phthalocyanine pigment and the naphthal cyanine pigmentare preferable.

The phthalocyanine pigment and the naphthal cyanine pigment have astructure having resistance to deterioration such as decomposition andthe like caused by heat or ultraviolet ray, thus increasing the numberof rewritings.

In view of chemical stability such as weatherability and heat resistanceand the like, the reversible thermosensitive recording material underthe present invention is especially preferred to be formed with variousmetals and various complexes.

Adding a singlet oxygen quencher is allowed for improving chemicalstability.

In general, the reversible thermosensitive recording material which isthe over sheet under the present invention is produced by sequentiallyforming, on the support, the recording layer and other necessary layers.The present invention is, however, not limited to the above, and otherproduction method as described below is allowed.

For example, the reversible thermosensitive recording material havingsequentially the reversible thermosensitive recording layer and theprotective layer on the support can be produced in the following steps:i) preparing a protective layer face to be disposed on the uppermostlayer and a peelable base sheet having high peelability, ii) applying acoating solution on the peelable base sheet to thereby form theprotective layer at first, iii) then, forming the thermosensitiverecording layer on the protective layer by a coating method, iv) then,adhering the support film to the thermosensitive recording layer, and v)finally, peeling the peelable base sheet.

The reversible thermosensitive recording material which is the oversheet under the present invention may be partly or entirely providedwith a coloring layer which has an arbitrary picture pattern made byprinting methods such as an offset print, a gravure print, and the like;by printers such as an inkjet printer, a heat transfer printer, asublimation printer, and the like; and the like. Moreover, an upperportion of the coloring layer may be partly or entirely provided with anOP (over print) varnish layer having, as main component thereof, asetting resin.

FIG. 3 and FIG. 4 show an example of the informationrecording-displaying card under the present invention, specifically, amethod of making an IC card having a print layer.

FIG. 3 is a cross sectional view of a layer structure before thepressing for forming the IC card. The IC card in FIG. 3 has thefollowing structure: An inlet sheet C is interposed between a first coresheet portion B1 and a second core sheet portion B2. Outside the firstcore sheet portion B1, there is provided an over sheet A which is sooverlapped with the first core sheet portion B1 that an over sheetsupport 103 contacts the first core sheet portion B1. Outside the secondcore sheet portion B2 on the opposite side, an outer layer sheet portionD is overlapped. Heating-pressing the over sheet A and the outer layersheet portion D from respective outsides thereof by means of aheating-pressing machine can form a layer body for the IC card.Hereinabove, the inlet sheet C has a sheet 118 which is provided with anon-contact IC chip 113 having an antenna coil 114. The outer layersheet portion D includes an outer layer sheet 119 having a magneticstripe layer 115 which has been temporality transferred in advance. Thefirst core sheet portion B1 includes a print layer 111 on the over sheetAs side of a white core sheet 116, while the second core sheet portionB2 includes a print layer 112 on the outer layer sheet portion D's sideof a white core sheet 117.

Then, removing a peelable base material 101 and subsequently cutting,with a punch blade, the layer structure into a card can form the ICcard. In the above method of removing the peelable base material 101 inthe final step allows the peelable base material 101 to function as aprotective film of the reversible thermosensitive recording layer 102.With this, the IC card in its manufacturing step can be free from i)scratches and ii) smear of heat press mirror plate which smear may becaused by bleed and the like from the reversible thermosensitiverecording layer 102.

The method in FIG. 3 of removing the peelable material 101 after theheating-pressing can be replaced with the following method. Removing inadvance the peelable base material 101 from the over sheet A,overlapping the over sheet A with the first core sheet portion B1,carrying out the heating-pressing as described above, and therebyforming the IC card. The over sheet having the thus obtained structurecan be treated like a thick over sheet which is used generally, therebya production line for the general card can be used. Moreover, an oversheet whose peelable base material is removed and which is rolled can beused.

Under the embodiment, the pressing condition is preferred to have apressing temperature in a range from 100° C. to 150° C., a pressingpressure in a range from 10 kgf/cm² to 50 kgf/cm², and a pressing timein a range from 5 minutes to 60 minutes.

The IC card formed by the heating-pressing as is seen in FIG. 3, afterbeing formed into the card, can be embossed (character) by means of anembosser. FIG. 4 shows the IC card having an emboss 120.

As the sheet material for a sheet provided with the non-contact IC chipequipped with the antenna coil, i) those substantially like the materialfor the above core sheet and the above outer layer sheet, ii) anengineering plastic, iii) and the like can be used. Especiallypreferable are the materials excellent in heat resistance. The antennacoil may be formed by carrying out printing of the above sheet or anetching of the above sheet. The IC card in FIG. 3 uses a sheet which isprovided with the non-contact chip and the like equipped with theantenna coil. The present invention is, however, not limited thereto. AnIC chip wired with an antenna coil is usable.

Information of the magnetic tape, the IC chip and the like which areinstalled on the IC card under the present invention can be read orwritten by the known conventional method (contact or non-contact),namely, reading stored information or writing new information isaccomplished.

The image processing method under the present invention may be added byany other step(s), as long as at least one of the displaying and erasingof the image is carried out by heating the surface of the imagedisplaying section of the information recording-displaying card underthe present invention.

For forming a coloring image on the reversible thermosensitive recordingmaterial which is the over sheet under the present invention, the oversheet is to be heated to a coloring temperature or over followed by arapid quenching.

Specifically, heating with the thermal head or the laser beam for ashort time may locally heat the recording layer, thus causing animmediate heat diffusion, leading to a rapid quenching. With this, acoloring state can be fixed.

On the other hand, decolorizing may be carried out by: i) heating forrelatively a long time by means of a proper heat source followed bycooling, or ii) temporarily heating at a temperature slightly lower thanthe coloring temperature. Heating for a long time may increasetemperature of an extensive area of the recording medium, thus delayingthe subsequent cooling. In this step, therefore, the decolorizing may becaused. In this heating method, a heat roller, a heat stamp, a hot air,a ceramic heater and the like may be used, otherwise, a thermal head maybe used for a long time heating. For heating the recording layer to thedecolorizing temperature range, decreasing an applied energy to slightlylower than a recording energy is preferred. In the above decreasing ofthe applied energy, a voltage applied to the thermal head or a pulsewidth to the thermal head is to be adjusted.

Using the above method, the thermal head alone can carry out therecording-erasing, thereby enabling so-called an over writing thatincludes erasing of the image and displaying of a new image. Examples ofthe recording unit include, other than an ordinary printer, a heattransfer printer, a sublimation printer, and the like. Erasing can becarried out by heating to the decolorizing temperature range by means ofa heat roller, a heat stamp, and the like.

The image processor under the present invention is not specificallylimited, as long as at least one of the following is provided: i) animage displaying unit for displaying the image to the informationrecording-displaying card under the present invention, ii) an imageerasing unit for erasing the image, and iii) an image displaying-erasingunit for displaying and erasing the image.

Examples of the image displaying unit include a thermal head, a lasersystem, and the like; while examples of the image erasing unit include athermal head, a ceramic heater, a heat roller, a heat stamp, a hot airmachine, and the like.

EXAMPLE

The information recording-displaying card under the present invention isto be described more in detail hereinafter based on examples. Theinformation recording-displaying card under the present invention is,however, not limited to descriptions in the examples.

Example 1

Form Barrier Layer

A support sheet (branded as DIAFIX PG-CHI made by Mitsubishi Plastics,Inc.) made of an amorphous aromatic polyester resin and having thicknessof 100 μm was prepared.

Then, a barrier layer was formed in the following steps: i) preparing adrawing PET film (branded as DIAFOIL K233E made by Mitsubishi Polyesterfilm Japan) having thickness of 4.5 μm, ii) coating one face of thedrawing PET film with a two-solution adhesive solution (namely,containing a urethane resin and an isocyanate crosslinking agent), iii)drying, iv) forming an adhesive layer having thickness of 1 μm, v)overlapping the drawing PET film (thickness of 4.5 μm) on the sheet madeof the amorphous aromatic polyester resin, to be followed by drylaminating, vi) aging the thus obtained sheet for 24 hours at anatmospheric temperature of 40° C., and vii) forming the barrier layer onthe support.

Form Reversible Recording Layer

The following dispersing solution was prepared for forming thereversible thermosensitive recording layer. The dispersing solution as acoating solution was applied on the barrier layer (the drawing PET film)with a wire bar, then was dried at 80° C. for 5 minutes. Then, curingwas carried out at 60° C. for 24 hours, to thereby form the reversiblethermosensitive recording layer having film thickness of about 10 μm.(Dispersing solution for reversible thermosensitive recording layer) 1)Developing agent having the following structural formula 4 parts

2) Dialkyl carbamide (branded as Hakreen SB made by 1 part Nihon KaseiCO., LTD.) 3) Acrylic polyol 50% solution 9 parts (branded as LR503 madeby Mitsubishi Rayon Co., Ltd.) 4) Methyl ethyl ketone 70 parts The abovecompositions were pulverized and dispersed by means of a ball mill intoparticles having an average particle diameter of about 1 μm. 5)2-anilino-3-methyl-6-dibutyl amino fluoran 1 part 6) Isocyanate (brandedas CORONATE HL made by 2 parts NIPPON POLYURETHANE INDUSTRY CO., LTD.)

The above compositions were put into a dispersing solution in whichdeveloping agent is pulverized and dispersed, followed by a sufficientstirring, to thereby prepare a recording layer coating solution.

Then, the following coating solution for forming the protective layerwas prepared. The coating solution was applied on the thus formedreversible thermosensitive recording layer, forming thickness of 2 μm.Then, an ultraviolet ray (conditions: 120 W/cm×10 m/min) was irradiatedfor setting. Then, aging was carried out at 60° C. for 16 hours, tothereby form the protective layer.

With the above steps, an over sheet was thus prepared having sequentiallayers of the support, the barrier layer, the reversible thermosensitiverecording layer, and the protective layer. (Coating solution for formingprotective layer) 1) Urethane acrylate ultraviolet setting resin 15parts (branded as C7-157 made by Dainippon Ink and ChemicalsIncorporated) 2) Filler (branded as P527 made by MIZUSAWA  5 partsINDUSTRIAL CHEMICALS, LTD.) 3) Ethyl acetate 85 parts

The above compositions were sufficiently dissolved-stirred, to therebyprepare the coating solution for forming the protective layer.

As the reversible recording property in the prescription structure, theerasable limit temperature is 170° C.

Example 2

In the preparation of the over sheet, the example 1 was likewise carriedout, except that the barrier layer was changed as follows:

A sheet made of an amorphous aromatic polyester resin (branded as DIAFIXPG-CHI made by Mitsubishi Plastics, Inc.) having thickness of 100 μm wasprepared. Barrier layer: a drawing PET film (branded as DIAFOIL K230Emade by Mitsubishi Polyester film Japan) having thickness of 6 μm wasused for a dry laminating on the above amorphous aromatic polyesterresin sheet.

Example 3

In the preparation of the over sheet, the example 1 was likewise carriedout, except that the barrier layer was changed as follows:

A sheet made of an amorphous aromatic polyester resin (branded as DIAFIXPG-CHI made by Mitsubishi Plastics, Inc.) having thickness of 100 μm wasprepared. Barrier layer: a drawing PET film (branded as DIAFOIL KC230-8Emade by Mitsubishi Polyester film Japan) having thickness of 8 μm wasused for a dry laminating on the above amorphous aromatic polyesterresin sheet.

Example 4

For preparing the over sheet, an amorphous aromatic polyester resinsheet (branded as DIAFIX PG-CHI made by Mitsubishi Plastics, Inc.)having thickness of 100 μm was prepared. On a surface of the thusprepared amorphous aromatic polyester resin sheet, the following coatingsolution for the barrier layer was applied by means of a bar coater.

Then, the example 1 was likewise carried out, except that an ultraviolet(160 W/cm×10 m/min) was irradiated for setting and that the barrierlayer had thickness of 2 μm. (Coating solution for barrier layer)Ultraviolet ray setting resin: 50 weight parts 5-function acrylatemonomer (branded as KAYARAD D-310 made by NIPPON KAYAKU CO., LTD.) Photopolymerization starting agent:  3 weight parts (branded as IRGACURE 184made by Chiba Speciality Chemicals) Coating solvent: 2-propanol 50weight parts

Example 5

As a peelable base material, a polyethylene terephthalate film(thickness of 38 μm) was prepared which had been coated in advance witha silicone resin on its surface.

To the above silicone-coated surface, an epoxy acrylate ultraviolet raysetting resin was applied, followed by irradiating of 160 W/cm of theultraviolet ray at 10 m/minute for setting, to thereby form a protectivelayer having thickness of 5 μm.

Then, the dispersing solution for the reversible thermosensitiverecording layer which solution was used in the example 1 was applied toa surface of the protective layer (namely, a layered body of peelablebase material and protective layer), then drying at 80° C. for 5minutes, and then aging at 60° C. for 24 hours, to thereby form areversible thermosensitive recording layer having thickness of 10 μmafter the drying.

To an amorphous aromatic polyester resin sheet (branded as DIAFIX PG-CHImade by Mitsubishi Plastics, Inc.) having thickness of 100 μm, therecording layer's side of a layered body (constituted of the peelablebase material, the protective layer, the reversible thermosensitiverecording layer which are thus obtained) was bonded (dry laminating), byusing 2-solution adhesive (namely, urethane resin and isocyanatecrosslinking agent).

After forming the layer structure of the peelable base material, theprotective layer, the reversible thermosensitive recording layer, andthe support, the peelable base material was peeled, to thereby obtainthe over sheet.

Example 6

For preparing the over sheet, a support sheet (prototype PETG/PC (9/1)made by Mitsubishi Plastics, Inc.) having thickness of 100 μm wasprepared which sheet contained a polymer alloy resin made of anamorphous aromatic polyester resin and a polycarbonate resin. Except forthe above preparation (change), the example 1 was likewise carried out,to thereby prepare the over sheet.

Example 7

For preparing the over sheet, a support sheet (prototype PETG/PC (7/3)made by Mitsubishi Plastics, Inc.) having thickness of 100 μm wasprepared which sheet contained a polymer alloy resin made of anamorphous aromatic polyester resin and a polycarbonate resin. Except forthe above preparation (change), the example 1 was likewise carried out,to thereby prepare the over sheet.

Example 8

The example 1 was likewise carried out, except that the developing agentof the dispersing solution for the reversible thermosensitive recordinglayer was changed to following compound, to thereby prepare aninformation recording-displaying card.

Comparative Example 1

The example 1 was likewise carried out, except that the barrier layerwas changed as follows in the preparation of the over sheet, to therebyprepare the over sheet:

An amorphous aromatic polyester resin sheet (branded as DIAFIX PG-CHImade by Mitsubishi Plastics, Inc.) having thickness of 100 μm wasprepared. Barrier layer: a drawing PET film (branded as DIAFOIL H100made by Mitsubishi Polyester film Japan) having thickness of 12 μm wasused for a dry laminating on the above amorphous aromatic polyesterresin sheet.

Comparative Example 2

The example 1 was likewise carried out, except that the barrier layerwas changed as follows in the preparation of the over sheet, to therebyprepare the over sheet:

An amorphous aromatic polyester resin sheet (branded as DIAFIX PG-CHImade by Mitsubishi Plastics, Inc.) having thickness of 100 μm wasprepared. Barrier layer: a drawing PET film (branded as DIAFOIL T100Emade by Mitsubishi Polyester film Japan) having thickness of 38 μm wasused for a dry laminating on the above amorphous aromatic polyesterresin sheet.

Comparative Example 3

The example 5 was likewise carried out, except for the following change,to thereby prepare the over sheet:

-   -   the amorphous aromatic polyester resin sheet having thickness of        100 μm was changed to:    -   a drawing PET having thickness of 125 μm.

Comparative Example 4

The example 5 was likewise carried out, except for the following change,to thereby prepare the over sheet:

-   -   the amorphous aromatic polyester resin sheet having thickness of        100 μm was changed to:    -   a vinyl chloride resin sheet having thickness of 100 μm.

Comparative Example 5

The example 1 was likewise carried out, except for the following change,to thereby prepare the over sheet:

-   -   the amorphous aromatic polyester resin sheet (branded as DIAFIX        PG-CHI made by Mitsubishi Plastics, Inc.) having thickness of        100 μm was changed to:    -   a direct layering of the reversible recording layer on the        amorphous aromatic polyester resin sheet, without any        intervention by a film or a barrier layer. In the applying of        the reversible recording layer, the amorphous aromatic polyester        resin sheet was eroded and then dried. Soon after the drying,        the over sheet was deformed, causing a rough surface thereof.        Prepare Information Recording-Displaying Card

As an outer layer sheet, an amorphous aromatic polyester resin sheet(branded as DIAFIX PG-CHI made by Mitsubishi Plastics, Inc.) havingthickness of 100 μm was prepared. As a core sheet, an amorphouspolyester sheet (branded as DIAFIX PG-WHI made by Mitsubishi Plastics,Inc.) having thickness of 280 μm was prepared.

The above outer layer sheet, the above core sheets and the over sheetsobtained in the examples, the comparative example 1, the comparativeexample 2, the comparative example 3 and the comparative example 5 werecut into a size of 300 mm×300 mm.

As is seen in FIG. 1A and FIG. 1B, two of the core sheets wereoverlapped on one outer layer sheet. Moreover, the over sheets preparedin the examples, the comparative example 1, the comparative example 2,the comparative example 3 and the comparative example 5 were disposedsuch that the support of the over sheet was overlapped on the twosheets. Then, the thus formed layers were interposed between chromiumplating plates not to cause drift (or displacement, shear, the like),followed by heating-pressing, to thereby unite the layers by fusion.

The heating temperature was 120° C., and the pressing pressure was 15kg/cm² (sheet face pressure), and the pressing time was 10 minutes. Thethus united sheet by fusion was cooled, taken out, subjected to apunching into a card configuration, to thereby prepare the informationrecording-displaying card.

Over sheet prepared in the example 4:

Like the above, the over sheet prepared in the example 4 was used forpreparing the information recording-displaying card, except that thecore sheet was a vinyl chloride sheet having thickness of 280 μm.

Evaluations of the over sheets and the information recording-displayingcards thus prepared were carried out, the results thereof being shown inthe following Table 1.

Evaluation Method:

(1) Surface Waviness

The surface wavinesses (5.0 mm of length) of the over sheets prepared inthe examples and the comparative examples were measured using a surfaceroughness-configuration measuring apparatus (made by TOKYO SEIMITSU).

(2) Storage Elasticity E′

The over sheets prepared in the examples and the comparative exampleswere measured using “Viscosity-Elasticity Spectrometer” made by IwamotoSeisakusho by carrying out a tensile test (temperature distribution ofdynamic viscosity) at a frequency of 1 Hz. An actual number was used forcalculating the storage elasticity E′.

(3) Measure Erasing Temperature of Over Sheet

A heat slope tester HG-100 (made by TOYO SEIKI KOGYO CO., LTD.) wasused. Conditions: 5° C. stepwise temperatures under a pressure of 1Kgf/cm for 1 second. A printing image reaching a saturated density waserased. Herein, a temperature of a coloring density of “less than orequal to texture density+0.02” was defined as an erasing temperature.

(4) Measure Rewriteability

A card printer R28000 (made by Kyushu Matsushita) was used. Printingconditions: 0.75 mJ. Heater bar temperature: 140° C. A thermal head wasused for printing of the information recording-displaying card thusprepared. Then, the thus printed section was heated by means of a heaterbar for erasing the print section. A print erasing section was visuallychecked based on the following criteria:

-   -   Criterion 1: No visible erasing remnant checked is defined as        “good.”    -   Criterion 2: Visible erasing remnant checked is defined as        “fair.”    -   Criterion 3: Obvious erasing remnant checked is defined as “not        acceptable.”        (5) Measure Embossability

The thus formed card was embossed by using a HAND EMBOSSER JIKEN NE-1000(made by NIHON JIKEN). The thus embossed card was checked for warp.

Criterion: Warp more than 2.5 mm was defined as “not acceptable.”

The embossing was carried out in a method specified in JIS X6301 and JIS6302.

The card's warp was measured in a method specified in JIS X6301 and JIS6305. The external view of the emboss was evaluated by visually checkingfor a crack of the over sheet or a peeling of the over sheet.

-   -   Criterion 1: Over sheet having no crack or peeling is defined as        “acceptable.”    -   Criterion 2: Over sheet having crack or peeling defined as “not        acceptable.”        (6) Environmental Property

The thus prepared information recording-displaying card was subjected toa burning, so as to check for dioxin.

-   -   Criterion 1: No dioxin is caused is defined as “acceptable.”

Criterion 2: Dioxin is caused is defined as “not acceptable.” TABLE 1Temp. of Base material for Base material for Type of Storage storageErasing over sheet core sheet barrier elesticity elesticity Wavinessupper limit Type Thickness (μm) Type Thickness (μm) layer E″ at 180° C.E″ (1.0 E + 08) (WcM) μm temp. Example 1 PG-CHI 100 PG-WHI 280 4.5 μmPET 2.5 × 10⁷ 110 6.84 170 Example 2 PG-CHI 100 PG-WHI 280   6 μm PET4.0 × 10⁷ 125 6.84 170 Example 3 PG-CHI 100 PG-WHI 280   8 μm PET 5.0 ×10⁷ 134 6.84 170 Example 4 PG-CHI 100 PG-WHI 280 3 μm UV layer 4.5 × 10⁷98 8.58 170 Example 5 PG-CHI 100 PG-WHI 280 — 1.0 × 10⁶ 81 6.84 170Example 6 PETG/PC 100 PG-WHI 280 4.5 μm PET 2.6 × 10⁷ 119 6.84 170 (9/1)Example 7 PETG/PC 100 PG-WHI 280 4.5 μm PET 3.0 × 10⁷ 136 6.84 170 (7/3)Example 8 PG-CHI 100 PG-WHI 280 4.5 μm PET 2.5 × 10⁷ 110 6.84 150Comparative PG-CHI 100 PG-WHI 280  12 μm PET 6.0 × 10⁷ 142 6.84 170example 1 Comparative PG-CHI 100 PG-WHI 280  38 μm PET 8.5 × 10⁷ 1706.84 170 example 2 Comparative T100E 100 C-4636 280 — 4.0 × 10⁸ >2006.84 170 example 3 Comparative C-8195 100 C-4636 280 — 1.0 × 10⁶ 80 6.84170 example 4 Comparative PG-CHI 100 PG-WHI 280 — 1.0 × 10⁶ 81 13.6 170example 5 Embossability External Card's warp view, crack, EnvironmentalTotal Eraseability (mm) peeling property evaluation Example 1 Acceptable2.2 Acceptable Acceptable Acceptable Example 2 Acceptable 2.0 AcceptableAcceptable Acceptable Example 3 Acceptable 2.0 Acceptable AcceptableAcceptable Example 4 Acceptable 2.4 Acceptable Acceptable AcceptableExample 5 Acceptable 1.9 Acceptable Acceptable Acceptable Example 6Acceptable 2.1 Acceptable Acceptable Acceptable Example 7 Acceptable 2.0Acceptable Acceptable Acceptable Example 8 Acceptable 2.2 AcceptableAcceptable Acceptable Comparative Not acceptable 28 (Not acceptable)Acceptable Acceptable Not acceptable example 1 Comparative Notacceptable 3.9 (Not acceptable) Not acceptable Acceptable Not acceptableexample 2 Comparative Not acceptable 3.7 (Not acceptable) Not acceptableAcceptable Not acceptable example 3 Comparative Acceptable 2.1Acceptable Not acceptable Not acceptable example 4 Comparative — — —Acceptable Not acceptable example 5

As evident from the detailed and specific description above, theinformation recording-displaying card and the over sheet under thepresent invention can be easily embossed, and are excellent in card'smachinability (by bonding to a thick base material of a reversiblethermosensitive recording medium) and in eraseability. In addition, theinformation recording-displaying card and the over sheet under thepresent invention are easy to scrap and dispose, causing noenvironmental pollution. Moreover, the method of forming the informationrecording-displaying card can form the image recording-displaying cardunder the present invention imparting thereto good quality.

Moreover, the present invention can provide an image processing methodand an image processor which are proper for manufacturing the imagerecording-displaying card under the present invention.

1. An information recording-displaying card, comprising: a core sheet;and an over sheet bonded to the core sheet, wherein the over sheetcomprises: a support which comprises an amorphous polyester resin, and areversible thermosensitive recording layer disposed on the support,wherein the reversible thermosensitive recording layer comprises: anelectron-donating coloring compound, and an electron-accepting compound,wherein the reversible thermosensitive recording layer is capable offorming a coloring state and a decolorizing state, with a difference inat least one of the following: a heating temperature, and a cooling rateafter a heating, and wherein the over sheet is embossable in an upperportion thereof, functions as an image displaying section, and meets thefollowing condition (A), condition (B) and condition (C): condition (A)(the over sheet's upper limit temperature for erasing−30° C.)>(the oversheet's temperature of a storage elasticity E′ (1.0 E+08) Pa), condition(B) 10 μm or less of a surface waviness, and condition (C) 1.0 E+02Pa≦(the storage elasticity E′ of the reversible thermosensitive oversheet at 180° C.)≦5.0 E+07 Pa.
 2. The information recording-displayingcard according to claim 1, wherein the temperature of the storageelasticity E′ (1.0 E+08) Pa of the over sheet is less than 140° C. 3.The information recording-displaying card according to claim 1, whereinthe over sheet is bonded to substantially an entire face of the coresheet.
 4. The information recording-displaying card according to claim1, wherein the support is one of the following: an amorphous polyesterresin, and a polymer alloy which comprises an amorphous polyester resinand a polycarbonate resin.
 5. The information recording-displaying cardaccording to claim 1, wherein a barrier layer is interposed between thesupport and the reversible thermosensitive recording layer.
 6. Theinformation recording-displaying card according to claim 5, wherein thebarrier layer is formed by bonding a resin film.
 7. The informationrecording-displaying card according to claim 6, wherein the resin filmof the barrier layer has a thickness of 8 μm or less.
 8. The informationrecording-displaying card according to claim 6, wherein the resin filmof the barrier layer is a polyester film subjected to a crystallizingtreatment.
 9. The information recording-displaying card according toclaim 5, wherein the barrier layer comprises, as a main componentthereof, a resin which is capable of at least one of the following:being soluble in at least one of an alcohol solvent and water, and beingdispersed in at least one of the alcohol solvent and the water.
 10. Theinformation recording-displaying card according to claim 1, wherein theelectron-donating coloring compound is a leuco dye.
 11. The informationrecording-displaying card according to claim 1, wherein theelectron-accepting compound is a phenol containing a straight chainhydrocarbon.
 12. The information recording-displaying card according toclaim 1, wherein the core sheet comprises at least a thermoplastic resinsheet having a thickness in a range from 0.05 mm to 5.00 mm.
 13. Theinformation recording-displaying card according to claim 12, wherein thecore sheet is made of a materiel which is substantially common to amaterial for the support constituting the over sheet.
 14. Theinformation recording-displaying card according to claim 1, wherein theinformation recording-displaying card comprises an information storingsection.
 15. The information recording-displaying card according toclaim 14, wherein the information storing section is one of thefollowing: a section which comprises a magnetic material as a mainmaterial, and an IC chip.
 16. The information recording-displaying cardaccording to claim 14, wherein the core sheet comprises a plurality ofthermoplastic resin sheets between which an IC chip is embedded, tothereby form the information storing section.
 17. The informationrecording-displaying card according to claim 14, wherein the over sheethas the information storing section which comprises, as a main materialtherefor, a magnetic material.
 18. The information recording-displayingcard according to claim 1, wherein the information recording-displayingcard has a mark formed through an embossing.
 19. The informationrecording-displaying card according to claim 18, wherein the mark formedthrough the embossing is disposed on the over sheet.
 20. A method ofmanufacturing an information recording-displaying card, comprising:heating-pressing a core sheet and an over sheet at a melting temperatureor less of an electron-accepting compound, to thereby bond the oversheet with the core sheet, wherein the over sheet comprises: a supportwhich comprises an amorphous polyester resin, and a reversiblethermosensitive recording layer disposed on the support, wherein thereversible thermosensitive recording layer comprises: anelectron-donating coloring compound, and the electron-acceptingcompound, wherein the reversible thermosensitive recording layer iscapable of forming a coloring state and a decolorizing state, with adifference in at least one of the following: a heating temperature, anda cooling rate after a heating, and wherein the over sheet is embossablein an upper portion thereof, functions as an image displaying section,and meets the following condition (A), condition (B) and condition (C):condition (A) (the over sheet's upper limit temperature for erasing−30°C.)>(the over sheet's temperature of a storage elasticity E′ (1.0 E+08)Pa), condition (B) 10 μm or less of a surface waviness, and condition(C) 1.0 E+02 Pa≦(the storage elasticity E′ of the reversiblethermosensitive over sheet at 180° C.)≦5.0 E+07 Pa.
 21. The method ofmanufacturing the information recording-displaying card according toclaim 20, wherein the heating-pressing is carried out at 150° C. orless, for bonding the over sheet with the core sheet.
 22. An over sheet,comprising: a support which comprises an amorphous polyester resin; anda reversible thermosensitive recording layer disposed on the support,wherein the reversible thermosensitive recording layer comprises: anelectron-donating coloring compound, and an electron-accepting compound,wherein the reversible thermosensitive recording layer is capable offorming a coloring state and a decolorizing state, with a difference inat least one of the following: a heating temperature, and a cooling rateafter a heating, and wherein the over sheet is embossable in an upperportion thereof, functions as an image displaying section, and meets thefollowing condition (A), condition (B) and condition (C): condition (A)(the over sheet's upper limit temperature for erasing−30° C.)>(the oversheet's temperature of a storage elasticity E′ (1.0 E+08) Pa), condition(B) 10 μm or less of a surface waviness, and condition (C) 1.0 E+02Pa≦(the storage elasticity E′ of the reversible thermosensitive oversheet at 180° C.)≦5.0 E+07 Pa.
 23. An image processing method,comprising: heating a surface of an image displaying section of aninformation recording-displaying card; and carrying out thereby at leastone of the following: displaying an image, and erasing the image,wherein the information recording-displaying card, comprises: a coresheet; an over sheet bonded to the core sheet, wherein the over sheetcomprises: a support which comprises an amorphous polyester resin, and areversible thermosensitive recording layer disposed on the support,wherein the reversible thermosensitive recording layer comprises: anelectron-donating coloring compound, and an electron-accepting compound,wherein the reversible thermosensitive recording layer is capable offorming a coloring state and a decolorizing state, with a difference inat least one of the following: a heating temperature, and a cooling rateafter a heating, and wherein the over sheet is embossable in an upperportion thereof, functions as an image displaying section, and meets thefollowing condition (A), condition (B) and condition (C): condition (A)(the over sheet's upper limit temperature for erasing−30° C.)>(the oversheet's temperature of a storage elasticity E′ (1.0 E+08) Pa), condition(B) 10 μm or less of a surface waviness, and condition (C) 1.0 E+02Pa≦(the storage elasticity E′ of the reversible thermosensitive oversheet at 180° C.)≦5.0 E+07 Pa.
 24. The image processing method accordingto claim 23, wherein a thermal head is used for the displaying of theimage.
 25. The image processing method according to claim 23, whereinone of a thermal head and a ceramic heater is used for the erasing ofthe image.
 26. The image processing method according to claim 23,wherein the thermal head is used for the displaying and the erasing ofthe image, and an over writing is carried out by the erasing of theimage and a displaying of a new image.
 27. An image processor,comprising: at least one of the following: an image displaying unit fordisplaying an image to an information recording-displaying card; animage erasing unit for erasing the image; and an imagedisplaying-erasing unit for displaying and erasing the image, whereinthe information recording-displaying card comprises: a core sheet; anover sheet bonded to the core sheet, wherein the over sheet comprises: asupport which comprises an amorphous polyester resin, and a reversiblethermosensitive recording layer disposed on the support, wherein thereversible thermosensitive recording layer comprises: anelectron-donating coloring compound, and an electron-accepting compound,wherein the reversible thermosensitive recording layer is capable offorming a coloring state and a decolorizing state, with a difference inat least one of the following: a heating temperature, and a cooling rateafter a heating, and wherein the over sheet is embossable in an upperportion thereof, functions as an image displaying section, and meets thefollowing condition (A), condition (B) and condition (C): condition (A)(the over sheet's upper limit temperature for erasing−30° C.)>(the oversheet's temperature of a storage elasticity E′ (1.0 E+08) Pa), condition(B) 10 μm or less of a surface waviness, and condition (C) 1.0 E+02Pa≦(the storage elasticity E′ of the reversible thermosensitive oversheet at 180° C.)≦5.0 E+07 Pa.
 28. The image processor according toclaim 27, wherein the image processor comprises at least the imagedisplaying unit, and the image displaying unit is a thermal head. 29.The image processor according to claim 27, wherein the image processorcomprises at least the image erasing unit, and the image erasing unit isone of a thermal head and a ceramic heater.